1 /* 2 * Copyright (c) 2018, 2024, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "cds/aotClassInitializer.hpp" 27 #include "cds/archiveBuilder.hpp" 28 #include "cds/archiveHeapLoader.hpp" 29 #include "cds/archiveHeapWriter.hpp" 30 #include "cds/archiveUtils.hpp" 31 #include "cds/cdsConfig.hpp" 32 #include "cds/cdsEnumKlass.hpp" 33 #include "cds/cdsHeapVerifier.hpp" 34 #include "cds/heapShared.hpp" 35 #include "cds/metaspaceShared.hpp" 36 #include "classfile/classLoaderData.hpp" 37 #include "classfile/classLoaderExt.hpp" 38 #include "classfile/javaClasses.inline.hpp" 39 #include "classfile/modules.hpp" 40 #include "classfile/stringTable.hpp" 41 #include "classfile/symbolTable.hpp" 42 #include "classfile/systemDictionary.hpp" 43 #include "classfile/systemDictionaryShared.hpp" 44 #include "classfile/vmClasses.hpp" 45 #include "classfile/vmSymbols.hpp" 46 #include "gc/shared/collectedHeap.hpp" 47 #include "gc/shared/gcLocker.hpp" 48 #include "gc/shared/gcVMOperations.hpp" 49 #include "logging/log.hpp" 50 #include "logging/logStream.hpp" 51 #include "memory/iterator.inline.hpp" 52 #include "memory/resourceArea.hpp" 53 #include "memory/universe.hpp" 54 #include "oops/compressedOops.inline.hpp" 55 #include "oops/fieldStreams.inline.hpp" 56 #include "oops/objArrayOop.inline.hpp" 57 #include "oops/oop.inline.hpp" 58 #include "oops/typeArrayOop.inline.hpp" 59 #include "prims/jvmtiExport.hpp" 60 #include "runtime/arguments.hpp" 61 #include "runtime/fieldDescriptor.inline.hpp" 62 #include "runtime/init.hpp" 63 #include "runtime/javaCalls.hpp" 64 #include "runtime/mutexLocker.hpp" 65 #include "runtime/safepointVerifiers.hpp" 66 #include "utilities/bitMap.inline.hpp" 67 #include "utilities/copy.hpp" 68 #if INCLUDE_G1GC 69 #include "gc/g1/g1CollectedHeap.hpp" 70 #endif 71 72 #if INCLUDE_CDS_JAVA_HEAP 73 74 struct ArchivableStaticFieldInfo { 75 const char* klass_name; 76 const char* field_name; 77 InstanceKlass* klass; 78 int offset; 79 BasicType type; 80 81 ArchivableStaticFieldInfo(const char* k, const char* f) 82 : klass_name(k), field_name(f), klass(nullptr), offset(0), type(T_ILLEGAL) {} 83 84 bool valid() { 85 return klass_name != nullptr; 86 } 87 }; 88 89 class HeapShared::ArchivingObjectMark : public StackObj { 90 public: 91 ArchivingObjectMark(oop obj) { 92 _trace->push(obj); 93 } 94 ~ArchivingObjectMark() { 95 _trace->pop(); 96 } 97 }; 98 99 class HeapShared::ContextMark : public StackObj { 100 ResourceMark rm; 101 public: 102 ContextMark(const char* c) : rm{} { 103 _context->push(c); 104 } 105 ~ContextMark() { 106 _context->pop(); 107 } 108 }; 109 110 bool HeapShared::_disable_writing = false; 111 DumpedInternedStrings *HeapShared::_dumped_interned_strings = nullptr; 112 113 size_t HeapShared::_alloc_count[HeapShared::ALLOC_STAT_SLOTS]; 114 size_t HeapShared::_alloc_size[HeapShared::ALLOC_STAT_SLOTS]; 115 size_t HeapShared::_total_obj_count; 116 size_t HeapShared::_total_obj_size; 117 118 #ifndef PRODUCT 119 #define ARCHIVE_TEST_FIELD_NAME "archivedObjects" 120 static Array<char>* _archived_ArchiveHeapTestClass = nullptr; 121 static const char* _test_class_name = nullptr; 122 static Klass* _test_class = nullptr; 123 static const ArchivedKlassSubGraphInfoRecord* _test_class_record = nullptr; 124 #endif 125 126 127 // 128 // If you add new entries to the following tables, you should know what you're doing! 129 // 130 131 static ArchivableStaticFieldInfo archive_subgraph_entry_fields[] = { 132 {"java/lang/Integer$IntegerCache", "archivedCache"}, 133 {"java/lang/Long$LongCache", "archivedCache"}, 134 {"java/lang/Byte$ByteCache", "archivedCache"}, 135 {"java/lang/Short$ShortCache", "archivedCache"}, 136 {"java/lang/Character$CharacterCache", "archivedCache"}, 137 {"java/util/jar/Attributes$Name", "KNOWN_NAMES"}, 138 {"sun/util/locale/BaseLocale", "constantBaseLocales"}, 139 {"jdk/internal/module/ArchivedModuleGraph", "archivedModuleGraph"}, 140 {"java/util/ImmutableCollections", "archivedObjects"}, 141 {"java/lang/ModuleLayer", "EMPTY_LAYER"}, 142 {"java/lang/module/Configuration", "EMPTY_CONFIGURATION"}, 143 {"jdk/internal/math/FDBigInteger", "archivedCaches"}, 144 {"java/lang/reflect/Proxy$ProxyBuilder", "archivedData"}, // FIXME -- requires AOTClassLinking 145 146 #ifndef PRODUCT 147 {nullptr, nullptr}, // Extra slot for -XX:ArchiveHeapTestClass 148 #endif 149 {nullptr, nullptr}, 150 }; 151 152 // full module graph 153 static ArchivableStaticFieldInfo fmg_archive_subgraph_entry_fields[] = { 154 {"jdk/internal/loader/ArchivedClassLoaders", "archivedClassLoaders"}, 155 {ARCHIVED_BOOT_LAYER_CLASS, ARCHIVED_BOOT_LAYER_FIELD}, 156 {"java/lang/Module$ArchivedData", "archivedData"}, 157 {nullptr, nullptr}, 158 }; 159 160 KlassSubGraphInfo* HeapShared::_default_subgraph_info; 161 ArchivedKlassSubGraphInfoRecord* HeapShared::_runtime_default_subgraph_info; 162 GrowableArrayCHeap<OopHandle, mtClassShared>* HeapShared::_pending_roots = nullptr; 163 GrowableArrayCHeap<oop, mtClassShared>* HeapShared::_trace = nullptr; 164 GrowableArrayCHeap<const char*, mtClassShared>* HeapShared::_context = nullptr; 165 GrowableArrayCHeap<OopHandle, mtClassShared>* HeapShared::_root_segments; 166 int HeapShared::_root_segment_max_size_elems; 167 OopHandle HeapShared::_scratch_basic_type_mirrors[T_VOID+1]; 168 MetaspaceObjToOopHandleTable* HeapShared::_scratch_java_mirror_table = nullptr; 169 MetaspaceObjToOopHandleTable* HeapShared::_scratch_references_table = nullptr; 170 171 static bool is_subgraph_root_class_of(ArchivableStaticFieldInfo fields[], InstanceKlass* ik) { 172 for (int i = 0; fields[i].valid(); i++) { 173 if (fields[i].klass == ik) { 174 return true; 175 } 176 } 177 return false; 178 } 179 180 bool HeapShared::is_subgraph_root_class(InstanceKlass* ik) { 181 return is_subgraph_root_class_of(archive_subgraph_entry_fields, ik) || 182 is_subgraph_root_class_of(fmg_archive_subgraph_entry_fields, ik); 183 } 184 185 unsigned HeapShared::oop_hash(oop const& p) { 186 // Do not call p->identity_hash() as that will update the 187 // object header. 188 return primitive_hash(cast_from_oop<intptr_t>(p)); 189 } 190 191 static void reset_states(oop obj, TRAPS) { 192 Handle h_obj(THREAD, obj); 193 InstanceKlass* klass = InstanceKlass::cast(obj->klass()); 194 TempNewSymbol method_name = SymbolTable::new_symbol("resetArchivedStates"); 195 Symbol* method_sig = vmSymbols::void_method_signature(); 196 197 while (klass != nullptr) { 198 Method* method = klass->find_method(method_name, method_sig); 199 if (method != nullptr) { 200 assert(method->is_private(), "must be"); 201 if (log_is_enabled(Debug, cds)) { 202 ResourceMark rm(THREAD); 203 log_debug(cds)(" calling %s", method->name_and_sig_as_C_string()); 204 } 205 JavaValue result(T_VOID); 206 JavaCalls::call_special(&result, h_obj, klass, 207 method_name, method_sig, CHECK); 208 } 209 klass = klass->java_super(); 210 } 211 } 212 213 void HeapShared::reset_archived_object_states(TRAPS) { 214 assert(CDSConfig::is_dumping_heap(), "dump-time only"); 215 log_debug(cds)("Resetting platform loader"); 216 reset_states(SystemDictionary::java_platform_loader(), CHECK); 217 log_debug(cds)("Resetting system loader"); 218 reset_states(SystemDictionary::java_system_loader(), CHECK); 219 220 // Clean up jdk.internal.loader.ClassLoaders::bootLoader(), which is not 221 // directly used for class loading, but rather is used by the core library 222 // to keep track of resources, etc, loaded by the null class loader. 223 // 224 // Note, this object is non-null, and is not the same as 225 // ClassLoaderData::the_null_class_loader_data()->class_loader(), 226 // which is null. 227 log_debug(cds)("Resetting boot loader"); 228 JavaValue result(T_OBJECT); 229 JavaCalls::call_static(&result, 230 vmClasses::jdk_internal_loader_ClassLoaders_klass(), 231 vmSymbols::bootLoader_name(), 232 vmSymbols::void_BuiltinClassLoader_signature(), 233 CHECK); 234 Handle boot_loader(THREAD, result.get_oop()); 235 reset_states(boot_loader(), CHECK); 236 } 237 238 HeapShared::ArchivedObjectCache* HeapShared::_archived_object_cache = nullptr; 239 240 bool HeapShared::has_been_archived(oop obj) { 241 assert(CDSConfig::is_dumping_heap(), "dump-time only"); 242 return archived_object_cache()->get(obj) != nullptr; 243 } 244 245 int HeapShared::append_root(oop obj) { 246 assert(CDSConfig::is_dumping_heap(), "dump-time only"); 247 248 // No GC should happen since we aren't scanning _pending_roots. 249 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); 250 251 if (UsePermanentHeapObjects && obj != nullptr) { 252 int n = get_archived_object_permanent_index_locked(obj); 253 assert(n >= 0, "must have been added"); 254 return n; 255 } 256 257 if (_pending_roots == nullptr) { 258 _pending_roots = new GrowableArrayCHeap<OopHandle, mtClassShared>(500); 259 } 260 261 OopHandle oh(Universe::vm_global(), obj); 262 return _pending_roots->append(oh); 263 } 264 265 objArrayOop HeapShared::root_segment(int segment_idx) { 266 if (CDSConfig::is_dumping_heap() && !CDSConfig::is_dumping_final_static_archive()) { 267 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); 268 if (!HeapShared::can_write()) { 269 return nullptr; 270 } 271 } else { 272 assert(CDSConfig::is_using_archive(), "must be"); 273 } 274 275 objArrayOop segment = (objArrayOop)_root_segments->at(segment_idx).resolve(); 276 assert(segment != nullptr, "should have been initialized"); 277 return segment; 278 } 279 280 inline unsigned int oop_handle_hash(const OopHandle& oh) { 281 oop o = oh.resolve(); 282 if (o == nullptr) { 283 return 0; 284 } else { 285 return o->identity_hash(); 286 } 287 } 288 289 inline bool oop_handle_equals(const OopHandle& a, const OopHandle& b) { 290 return a.resolve() == b.resolve(); 291 } 292 293 class OrigToScratchObjectTable: public ResourceHashtable<OopHandle, OopHandle, 294 36137, // prime number 295 AnyObj::C_HEAP, 296 mtClassShared, 297 oop_handle_hash, 298 oop_handle_equals> {}; 299 300 static OrigToScratchObjectTable* _orig_to_scratch_object_table = nullptr; 301 302 void HeapShared::track_scratch_object(oop orig_obj, oop scratch_obj) { 303 MutexLocker ml(ArchivedObjectTables_lock, Mutex::_no_safepoint_check_flag); 304 if (_orig_to_scratch_object_table == nullptr) { 305 _orig_to_scratch_object_table = new (mtClass)OrigToScratchObjectTable(); 306 } 307 308 OopHandle orig_h(Universe::vm_global(), orig_obj); 309 OopHandle scratch_h(Universe::vm_global(), scratch_obj); 310 _orig_to_scratch_object_table->put_when_absent(orig_h, scratch_h); 311 } 312 313 oop HeapShared::orig_to_scratch_object(oop orig_obj) { 314 MutexLocker ml(ArchivedObjectTables_lock, Mutex::_no_safepoint_check_flag); 315 if (_orig_to_scratch_object_table != nullptr) { 316 OopHandle orig(&orig_obj); 317 OopHandle* v = _orig_to_scratch_object_table->get(orig); 318 if (v != nullptr) { 319 return v->resolve(); 320 } 321 } 322 return nullptr; 323 } 324 325 class ArchivedObjectPermanentIndexTable: public ResourceHashtable<OopHandle, int, 326 36137, // prime number 327 AnyObj::C_HEAP, 328 mtClassShared, 329 oop_handle_hash, 330 oop_handle_equals> {}; 331 332 static ArchivedObjectPermanentIndexTable* _permanent_index_table = nullptr; 333 334 void HeapShared::add_to_permanent_index_table(oop obj) { 335 assert_locked_or_safepoint(ArchivedObjectTables_lock); 336 337 assert(CDSConfig::is_dumping_heap(), "must be"); 338 if (UsePermanentHeapObjects) { 339 if (_permanent_index_table == nullptr) { 340 _permanent_index_table = new (mtClass)ArchivedObjectPermanentIndexTable(); 341 } 342 if (_pending_roots == nullptr) { 343 _pending_roots = new GrowableArrayCHeap<OopHandle, mtClassShared>(500); 344 } 345 346 if (_orig_to_scratch_object_table != nullptr) { 347 OopHandle orig(&obj); 348 OopHandle* v = _orig_to_scratch_object_table->get(orig); 349 if (v != nullptr) { 350 obj = v->resolve(); 351 } 352 } 353 354 OopHandle oh(Universe::vm_global(), obj); 355 int index = _pending_roots->append(oh); 356 _permanent_index_table->put_when_absent(oh, index); 357 } 358 } 359 360 int HeapShared::get_archived_object_permanent_index(oop obj) { 361 MutexLocker ml(ArchivedObjectTables_lock, Mutex::_no_safepoint_check_flag); 362 return get_archived_object_permanent_index_locked(obj); 363 } 364 365 // Can be called in the "old" workflow. 366 int HeapShared::get_archived_object_permanent_index_locked(oop obj) { 367 assert_locked_or_safepoint(ArchivedObjectTables_lock); 368 if (!UsePermanentHeapObjects) { 369 return -1; 370 } 371 if (!CDSConfig::is_dumping_heap() && !ArchiveHeapLoader::is_in_use()) { 372 return -1; 373 } 374 375 if (_permanent_index_table == nullptr) { 376 if (!ArchiveHeapLoader::is_in_use()) { 377 // Called in the old workflow 378 return -1; 379 } else { 380 _permanent_index_table = new (mtClass)ArchivedObjectPermanentIndexTable(); 381 int count = 0; 382 for (int segment_idx = 0; segment_idx < _root_segments->length(); segment_idx++) { 383 objArrayOop segment = (objArrayOop)_root_segments->at(segment_idx).resolve(); 384 for (int i = 0; i < segment->length(); i++, count++) { 385 oop root = segment->obj_at(i); 386 if (root != nullptr) { 387 OopHandle tmp(Universe::vm_global(), root); 388 int index = count; 389 _permanent_index_table->put_when_absent(tmp, index); 390 } 391 } 392 } 393 } 394 } 395 396 if (_orig_to_scratch_object_table != nullptr) { 397 OopHandle orig(&obj); 398 OopHandle* v = _orig_to_scratch_object_table->get(orig); 399 if (v != nullptr) { 400 obj = v->resolve(); 401 } 402 } 403 404 OopHandle tmp(&obj); 405 int* v = _permanent_index_table->get(tmp); 406 if (v != nullptr) { 407 int n = *v; 408 return n; 409 } 410 411 return -1; 412 } 413 414 oop HeapShared::get_archived_object(int permanent_index) { 415 if (ArchiveHeapLoader::is_in_use()) { 416 return get_root(permanent_index); 417 } else { 418 assert(CDSConfig::is_dumping_heap(), "must be"); 419 if (_pending_roots != nullptr) { 420 return _pending_roots->at(permanent_index).resolve(); 421 } else { 422 return nullptr; 423 } 424 } 425 } 426 427 void HeapShared::get_segment_indexes(int idx, int& seg_idx, int& int_idx) { 428 assert(_root_segment_max_size_elems > 0, "sanity"); 429 430 // Try to avoid divisions for the common case. 431 if (idx < _root_segment_max_size_elems) { 432 seg_idx = 0; 433 int_idx = idx; 434 } else { 435 seg_idx = idx / _root_segment_max_size_elems; 436 int_idx = idx % _root_segment_max_size_elems; 437 } 438 439 assert(idx == seg_idx * _root_segment_max_size_elems + int_idx, 440 "sanity: %d index maps to %d segment and %d internal", idx, seg_idx, int_idx); 441 } 442 443 // Returns an objArray that contains all the roots of the archived objects 444 oop HeapShared::get_root(int index, bool clear) { 445 assert(index >= 0, "sanity"); 446 assert(!CDSConfig::is_dumping_heap() && CDSConfig::is_using_archive(), "runtime only"); 447 assert(!_root_segments->is_empty(), "must have loaded shared heap"); 448 int seg_idx, int_idx; 449 get_segment_indexes(index, seg_idx, int_idx); 450 oop result = root_segment(seg_idx)->obj_at(int_idx); 451 if (clear) { 452 clear_root(index); 453 } 454 return result; 455 } 456 457 void HeapShared::clear_root(int index) { 458 assert(index >= 0, "sanity"); 459 assert(CDSConfig::is_using_archive(), "must be"); 460 if (ArchiveHeapLoader::is_in_use()) { 461 int seg_idx, int_idx; 462 get_segment_indexes(index, seg_idx, int_idx); 463 if (log_is_enabled(Debug, cds, heap)) { 464 oop old = root_segment(seg_idx)->obj_at(int_idx); 465 log_debug(cds, heap)("Clearing root %d: was " PTR_FORMAT, index, p2i(old)); 466 } 467 root_segment(seg_idx)->obj_at_put(int_idx, nullptr); 468 } 469 } 470 471 bool HeapShared::archive_object(oop obj) { 472 assert(CDSConfig::is_dumping_heap(), "dump-time only"); 473 474 assert(!obj->is_stackChunk(), "do not archive stack chunks"); 475 if (has_been_archived(obj)) { 476 return true; 477 } 478 479 if (ArchiveHeapWriter::is_too_large_to_archive(obj->size())) { 480 log_debug(cds, heap)("Cannot archive, object (" PTR_FORMAT ") is too large: " SIZE_FORMAT, 481 p2i(obj), obj->size()); 482 debug_trace(); 483 return false; 484 } else { 485 add_to_permanent_index_table(obj); 486 count_allocation(obj->size()); 487 ArchiveHeapWriter::add_source_obj(obj); 488 CachedOopInfo info = make_cached_oop_info(obj); 489 archived_object_cache()->put_when_absent(obj, info); 490 archived_object_cache()->maybe_grow(); 491 mark_native_pointers(obj); 492 493 if (log_is_enabled(Debug, cds, heap)) { 494 ResourceMark rm; 495 LogTarget(Debug, cds, heap) log; 496 LogStream out(log); 497 out.print("Archived heap object " PTR_FORMAT " : %s ", 498 p2i(obj), obj->klass()->external_name()); 499 if (java_lang_Class::is_instance(obj)) { 500 Klass* k = java_lang_Class::as_Klass(obj); 501 if (k != nullptr) { 502 out.print("%s", k->external_name()); 503 } else { 504 out.print("primitive"); 505 } 506 } 507 out.cr(); 508 } 509 510 if (java_lang_Module::is_instance(obj) && Modules::check_archived_module_oop(obj)) { 511 Modules::update_oops_in_archived_module(obj, append_root(obj)); 512 } 513 514 return true; 515 } 516 } 517 518 class MetaspaceObjToOopHandleTable: public ResourceHashtable<MetaspaceObj*, OopHandle, 519 36137, // prime number 520 AnyObj::C_HEAP, 521 mtClassShared> { 522 public: 523 oop get_oop(MetaspaceObj* ptr) { 524 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag); 525 OopHandle* handle = get(ptr); 526 if (handle != nullptr) { 527 return handle->resolve(); 528 } else { 529 return nullptr; 530 } 531 } 532 void set_oop(MetaspaceObj* ptr, oop o) { 533 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag); 534 OopHandle handle(Universe::vm_global(), o); 535 bool is_new = put(ptr, handle); 536 assert(is_new, "cannot set twice"); 537 } 538 void remove_oop(MetaspaceObj* ptr) { 539 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag); 540 OopHandle* handle = get(ptr); 541 if (handle != nullptr) { 542 handle->release(Universe::vm_global()); 543 remove(ptr); 544 } 545 } 546 }; 547 548 void HeapShared::add_scratch_resolved_references(ConstantPool* src, objArrayOop dest) { 549 if (_scratch_references_table == nullptr) { 550 _scratch_references_table = new (mtClass)MetaspaceObjToOopHandleTable(); 551 } 552 _scratch_references_table->set_oop(src, dest); 553 } 554 555 objArrayOop HeapShared::scratch_resolved_references(ConstantPool* src) { 556 return (objArrayOop)_scratch_references_table->get_oop(src); 557 } 558 559 void HeapShared::init_scratch_objects(TRAPS) { 560 for (int i = T_BOOLEAN; i < T_VOID+1; i++) { 561 BasicType bt = (BasicType)i; 562 if (!is_reference_type(bt)) { 563 oop m = java_lang_Class::create_basic_type_mirror(type2name(bt), bt, CHECK); 564 _scratch_basic_type_mirrors[i] = OopHandle(Universe::vm_global(), m); 565 track_scratch_object(Universe::java_mirror(bt), m); 566 } 567 } 568 _scratch_java_mirror_table = new (mtClass)MetaspaceObjToOopHandleTable(); 569 if (_scratch_references_table == nullptr) { 570 _scratch_references_table = new (mtClass)MetaspaceObjToOopHandleTable(); 571 } 572 } 573 574 // Given java_mirror that represents a (primitive or reference) type T, 575 // return the "scratch" version that represents the same type T. 576 // Note that if java_mirror will be returned if it's already a 577 // scratch mirror. 578 // 579 // See java_lang_Class::create_scratch_mirror() for more info. 580 oop HeapShared::scratch_java_mirror(oop java_mirror) { 581 assert(java_lang_Class::is_instance(java_mirror), "must be"); 582 583 for (int i = T_BOOLEAN; i < T_VOID+1; i++) { 584 BasicType bt = (BasicType)i; 585 if (!is_reference_type(bt)) { 586 if (_scratch_basic_type_mirrors[i].resolve() == java_mirror) { 587 return java_mirror; 588 } 589 } 590 } 591 592 if (java_lang_Class::is_primitive(java_mirror)) { 593 return scratch_java_mirror(java_lang_Class::as_BasicType(java_mirror)); 594 } else { 595 return scratch_java_mirror(java_lang_Class::as_Klass(java_mirror)); 596 } 597 } 598 599 oop HeapShared::scratch_java_mirror(BasicType t) { 600 assert((uint)t < T_VOID+1, "range check"); 601 assert(!is_reference_type(t), "sanity"); 602 return _scratch_basic_type_mirrors[t].resolve(); 603 } 604 605 oop HeapShared::scratch_java_mirror(Klass* k) { 606 return _scratch_java_mirror_table->get_oop(k); 607 } 608 609 void HeapShared::set_scratch_java_mirror(Klass* k, oop mirror) { 610 track_scratch_object(k->java_mirror(), mirror); 611 _scratch_java_mirror_table->set_oop(k, mirror); 612 } 613 614 void HeapShared::remove_scratch_objects(Klass* k) { 615 _scratch_java_mirror_table->remove_oop(k); 616 if (k->is_instance_klass()) { 617 _scratch_references_table->remove(InstanceKlass::cast(k)->constants()); 618 } 619 oop mirror = k->java_mirror(); 620 if (mirror != nullptr) { 621 OopHandle tmp(&mirror); 622 OopHandle* v = _orig_to_scratch_object_table->get(tmp); 623 if (v != nullptr) { 624 oop scratch_mirror = v->resolve(); 625 java_lang_Class::set_klass(scratch_mirror, nullptr); 626 _orig_to_scratch_object_table->remove(tmp); 627 } 628 } 629 } 630 631 bool HeapShared::is_lambda_form_klass(InstanceKlass* ik) { 632 return ik->is_hidden() && 633 (ik->name()->starts_with("java/lang/invoke/LambdaForm$MH+") || 634 ik->name()->starts_with("java/lang/invoke/LambdaForm$DMH+") || 635 ik->name()->starts_with("java/lang/invoke/LambdaForm$BMH+")); 636 } 637 638 bool HeapShared::is_lambda_proxy_klass(InstanceKlass* ik) { 639 return ik->is_hidden() && (ik->name()->index_of_at(0, "$$Lambda+", 9) > 0); 640 } 641 642 bool HeapShared::is_archivable_hidden_klass(InstanceKlass* ik) { 643 return CDSConfig::is_dumping_invokedynamic() && (is_lambda_form_klass(ik) || is_lambda_proxy_klass(ik)); 644 } 645 646 void HeapShared::copy_aot_initialized_mirror(Klass* orig_k, oop orig_mirror, oop m) { 647 if (!orig_k->is_instance_klass()) { 648 return; 649 } 650 InstanceKlass* ik = InstanceKlass::cast(orig_k); 651 652 if (HeapShared::is_archivable_hidden_klass(ik)) { 653 // We can't rerun the <clinit> method of hidden classes as we don't save 654 // the classData, so we must archive its mirror in initialized state. 655 assert(ik->is_initialized(), "must be"); 656 } 657 658 if (!ik->is_initialized() || !AOTClassInitializer::can_archive_initialized_mirror(ik)) { 659 return; 660 } 661 662 int nfields = 0; 663 for (JavaFieldStream fs(ik); !fs.done(); fs.next()) { 664 if (fs.access_flags().is_static()) { 665 fieldDescriptor& fd = fs.field_descriptor(); 666 int offset = fd.offset(); 667 switch (fd.field_type()) { 668 case T_OBJECT: 669 case T_ARRAY: 670 m->obj_field_put(offset, orig_mirror->obj_field(offset)); 671 break; 672 case T_BOOLEAN: 673 m->bool_field_put(offset, orig_mirror->bool_field(offset)); 674 break; 675 case T_BYTE: 676 m->byte_field_put(offset, orig_mirror->byte_field(offset)); 677 break; 678 case T_SHORT: 679 m->short_field_put(offset, orig_mirror->short_field(offset)); 680 break; 681 case T_CHAR: 682 m->char_field_put(offset, orig_mirror->char_field(offset)); 683 break; 684 case T_INT: 685 m->int_field_put(offset, orig_mirror->int_field(offset)); 686 break; 687 case T_LONG: 688 m->long_field_put(offset, orig_mirror->long_field(offset)); 689 break; 690 case T_FLOAT: 691 m->float_field_put(offset, orig_mirror->float_field(offset)); 692 break; 693 case T_DOUBLE: 694 m->double_field_put(offset, orig_mirror->double_field(offset)); 695 break; 696 default: 697 ShouldNotReachHere(); 698 } 699 nfields ++; 700 } 701 } 702 703 java_lang_Class::set_class_data(m, java_lang_Class::class_data(orig_mirror)); 704 705 // Class::reflectData use SoftReference, which cannot be archived. Set it 706 // to null and it will be recreated at runtime. 707 java_lang_Class::set_reflection_data(m, nullptr); 708 709 if (log_is_enabled(Info, cds, init)) { 710 ResourceMark rm; 711 log_debug(cds, init)("copied %3d field(s) in preinitialized mirror %s%s", nfields, ik->external_name(), 712 ik->is_hidden() ? " (hidden)" : ""); 713 } 714 715 InstanceKlass* buffered_ik = ArchiveBuilder::current()->get_buffered_addr(ik); 716 buffered_ik->set_has_preinitialized_mirror(); 717 } 718 719 static void copy_java_mirror_hashcode(oop orig_mirror, oop scratch_m) { 720 int src_hash = orig_mirror->identity_hash(); 721 scratch_m->set_mark(markWord::prototype().copy_set_hash(src_hash)); 722 assert(scratch_m->mark().is_unlocked(), "sanity"); 723 724 DEBUG_ONLY(int archived_hash = scratch_m->identity_hash()); 725 assert(src_hash == archived_hash, "Java mirror wrong hash: original %x, scratch %x", src_hash, archived_hash); 726 } 727 728 void HeapShared::archive_java_mirrors() { 729 AOTClassInitializer::reset_preinit_check(); 730 731 _orig_to_scratch_object_table->iterate([&](OopHandle o, OopHandle s) { 732 copy_java_mirror_hashcode(o.resolve(), s.resolve()); 733 return true; 734 }); 735 736 for (int i = T_BOOLEAN; i < T_VOID+1; i++) { 737 BasicType bt = (BasicType)i; 738 if (!is_reference_type(bt)) { 739 oop orig_mirror = Universe::java_mirror(bt); 740 oop m = _scratch_basic_type_mirrors[i].resolve(); 741 assert(m != nullptr, "sanity"); 742 bool success = archive_reachable_objects_from(1, _default_subgraph_info, m); 743 assert(success, "sanity"); 744 745 log_trace(cds, heap, mirror)( 746 "Archived %s mirror object from " PTR_FORMAT, 747 type2name(bt), p2i(m)); 748 749 Universe::set_archived_basic_type_mirror_index(bt, append_root(m)); 750 } 751 } 752 753 GrowableArray<Klass*>* klasses = ArchiveBuilder::current()->klasses(); 754 assert(klasses != nullptr, "sanity"); 755 756 for (int i = 0; i < klasses->length(); i++) { 757 Klass* orig_k = klasses->at(i); 758 oop orig_mirror = orig_k->java_mirror(); 759 oop m = scratch_java_mirror(orig_k); 760 if (m != nullptr) { 761 copy_aot_initialized_mirror(orig_k, orig_mirror, m); 762 if (CDSConfig::is_dumping_reflection_data() && java_lang_Class::has_reflection_data(orig_mirror)) { 763 oop reflection_data = java_lang_Class::reflection_data(orig_mirror); 764 bool success = archive_reachable_objects_from(1, _default_subgraph_info, reflection_data); 765 guarantee(success, ""); 766 java_lang_Class::set_reflection_data(m, reflection_data); 767 } 768 } 769 } 770 771 for (int i = 0; i < klasses->length(); i++) { 772 Klass* orig_k = klasses->at(i); 773 oop orig_mirror = orig_k->java_mirror(); 774 oop m = scratch_java_mirror(orig_k); 775 if (m != nullptr) { 776 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(orig_k); 777 bool success = archive_reachable_objects_from(1, _default_subgraph_info, m); 778 guarantee(success, "scratch mirrors must point to only archivable objects"); 779 buffered_k->set_archived_java_mirror(append_root(m)); 780 ResourceMark rm; 781 log_trace(cds, heap, mirror)( 782 "Archived %s mirror object from " PTR_FORMAT, 783 buffered_k->external_name(), p2i(m)); 784 785 // archive the resolved_referenes array 786 if (buffered_k->is_instance_klass()) { 787 InstanceKlass* ik = InstanceKlass::cast(buffered_k); 788 oop rr = ik->constants()->prepare_resolved_references_for_archiving(); 789 if (rr != nullptr && !ArchiveHeapWriter::is_too_large_to_archive(rr)) { 790 bool success = HeapShared::archive_reachable_objects_from(1, _default_subgraph_info, rr); 791 assert(success, "must be"); 792 int root_index = append_root(rr); 793 ik->constants()->cache()->set_archived_references(root_index); 794 } 795 } 796 } 797 } 798 } 799 800 void HeapShared::archive_strings() { 801 oop shared_strings_array = StringTable::init_shared_table(_dumped_interned_strings); 802 bool success = archive_reachable_objects_from(1, _default_subgraph_info, shared_strings_array); 803 // We must succeed because: 804 // - _dumped_interned_strings do not contain any large strings. 805 // - StringTable::init_shared_table() doesn't create any large arrays. 806 assert(success, "shared strings array must not point to arrays or strings that are too large to archive"); 807 StringTable::set_shared_strings_array_index(append_root(shared_strings_array)); 808 } 809 810 int HeapShared::archive_exception_instance(oop exception) { 811 bool success = archive_reachable_objects_from(1, _default_subgraph_info, exception); 812 assert(success, "sanity"); 813 return append_root(exception); 814 } 815 816 void HeapShared::mark_native_pointers(oop orig_obj) { 817 if (java_lang_Class::is_instance(orig_obj)) { 818 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::klass_offset()); 819 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::array_klass_offset()); 820 } else if (java_lang_invoke_ResolvedMethodName::is_instance(orig_obj)) { 821 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_invoke_ResolvedMethodName::vmtarget_offset()); 822 } 823 } 824 825 void HeapShared::get_pointer_info(oop src_obj, bool& has_oop_pointers, bool& has_native_pointers) { 826 CachedOopInfo* info = archived_object_cache()->get(src_obj); 827 assert(info != nullptr, "must be"); 828 has_oop_pointers = info->has_oop_pointers(); 829 has_native_pointers = info->has_native_pointers(); 830 } 831 832 void HeapShared::set_has_native_pointers(oop src_obj) { 833 CachedOopInfo* info = archived_object_cache()->get(src_obj); 834 assert(info != nullptr, "must be"); 835 info->set_has_native_pointers(); 836 } 837 838 void HeapShared::start_finding_archivable_hidden_classes() { 839 NoSafepointVerifier nsv; 840 841 init_seen_objects_table(); 842 843 find_archivable_hidden_classes_helper(archive_subgraph_entry_fields); 844 if (CDSConfig::is_dumping_full_module_graph()) { 845 find_archivable_hidden_classes_helper(fmg_archive_subgraph_entry_fields); 846 } 847 } 848 849 void HeapShared::end_finding_archivable_hidden_classes() { 850 NoSafepointVerifier nsv; 851 852 delete_seen_objects_table(); 853 } 854 855 void HeapShared::find_archivable_hidden_classes_helper(ArchivableStaticFieldInfo fields[]) { 856 if (!CDSConfig::is_dumping_heap()) { 857 return; 858 } 859 for (int i = 0; fields[i].valid(); ) { 860 ArchivableStaticFieldInfo* info = &fields[i]; 861 const char* klass_name = info->klass_name; 862 for (; fields[i].valid(); i++) { 863 ArchivableStaticFieldInfo* f = &fields[i]; 864 if (f->klass_name != klass_name) { 865 break; 866 } 867 868 InstanceKlass* k = f->klass; 869 oop m = k->java_mirror(); 870 oop o = m->obj_field(f->offset); 871 if (o != nullptr) { 872 find_archivable_hidden_classes_in_object(o); 873 } 874 } 875 } 876 } 877 878 class HeapShared::FindHiddenClassesOopClosure: public BasicOopIterateClosure { 879 GrowableArray<oop> _stack; 880 template <class T> void do_oop_work(T *p) { 881 // Recurse on a GrowableArray to avoid overflowing the C stack. 882 oop o = RawAccess<>::oop_load(p); 883 if (o != nullptr) { 884 _stack.append(o); 885 } 886 } 887 888 public: 889 890 void do_oop(narrowOop *p) { FindHiddenClassesOopClosure::do_oop_work(p); } 891 void do_oop( oop *p) { FindHiddenClassesOopClosure::do_oop_work(p); } 892 893 FindHiddenClassesOopClosure(oop o) { 894 _stack.append(o); 895 } 896 oop pop() { 897 if (_stack.length() == 0) { 898 return nullptr; 899 } else { 900 return _stack.pop(); 901 } 902 } 903 }; 904 905 void HeapShared::find_archivable_hidden_classes_in_object(oop root) { 906 ResourceMark rm; 907 FindHiddenClassesOopClosure c(root); 908 oop o; 909 while ((o = c.pop()) != nullptr) { 910 if (!has_been_seen_during_subgraph_recording(o)) { 911 set_has_been_seen_during_subgraph_recording(o); 912 913 if (java_lang_Class::is_instance(o)) { 914 Klass* k = java_lang_Class::as_Klass(o); 915 if (k != nullptr && k->is_instance_klass()) { 916 SystemDictionaryShared::mark_required_class(InstanceKlass::cast(k)); 917 } 918 } else if (java_lang_invoke_ResolvedMethodName::is_instance(o)) { 919 Method* m = java_lang_invoke_ResolvedMethodName::vmtarget(o); 920 if (m != nullptr && m->method_holder() != nullptr) { 921 SystemDictionaryShared::mark_required_class(m->method_holder()); 922 } 923 } 924 925 o->oop_iterate(&c); 926 } 927 } 928 } 929 930 void HeapShared::archive_objects(ArchiveHeapInfo *heap_info) { 931 { 932 NoSafepointVerifier nsv; 933 934 _default_subgraph_info = init_subgraph_info(vmClasses::Object_klass(), false); 935 _trace = new GrowableArrayCHeap<oop, mtClassShared>(250); 936 _context = new GrowableArrayCHeap<const char*, mtClassShared>(250); 937 938 // Cache for recording where the archived objects are copied to 939 create_archived_object_cache(); 940 941 if (UseCompressedOops || UseG1GC) { 942 log_info(cds)("Heap range = [" PTR_FORMAT " - " PTR_FORMAT "]", 943 UseCompressedOops ? p2i(CompressedOops::begin()) : 944 p2i((address)G1CollectedHeap::heap()->reserved().start()), 945 UseCompressedOops ? p2i(CompressedOops::end()) : 946 p2i((address)G1CollectedHeap::heap()->reserved().end())); 947 } 948 copy_objects(); 949 950 if (!SkipArchiveHeapVerification) { 951 CDSHeapVerifier::verify(); 952 } 953 check_default_subgraph_classes(); 954 } 955 956 GrowableArrayCHeap<oop, mtClassShared>* roots = new GrowableArrayCHeap<oop, mtClassShared>(_pending_roots->length()); 957 for (int i = 0; i < _pending_roots->length(); i++) { 958 roots->append(_pending_roots->at(i).resolve()); 959 } 960 ArchiveHeapWriter::write(roots, heap_info); 961 } 962 963 void HeapShared::copy_interned_strings() { 964 init_seen_objects_table(); 965 966 auto copier = [&] (oop s, bool value_ignored) { 967 assert(s != nullptr, "sanity"); 968 assert(!ArchiveHeapWriter::is_string_too_large_to_archive(s), "large strings must have been filtered"); 969 bool success = archive_reachable_objects_from(1, _default_subgraph_info, s); 970 assert(success, "must be"); 971 // Prevent string deduplication from changing the value field to 972 // something not in the archive. 973 java_lang_String::set_deduplication_forbidden(s); 974 }; 975 _dumped_interned_strings->iterate_all(copier); 976 977 delete_seen_objects_table(); 978 } 979 980 void HeapShared::copy_special_objects() { 981 // Archive special objects that do not belong to any subgraphs 982 init_seen_objects_table(); 983 archive_java_mirrors(); 984 archive_strings(); 985 Universe::archive_exception_instances(); 986 delete_seen_objects_table(); 987 } 988 989 void HeapShared::copy_objects() { 990 assert(HeapShared::can_write(), "must be"); 991 992 copy_interned_strings(); 993 copy_special_objects(); 994 995 archive_object_subgraphs(archive_subgraph_entry_fields, 996 false /* is_full_module_graph */); 997 998 if (CDSConfig::is_dumping_full_module_graph()) { 999 archive_object_subgraphs(fmg_archive_subgraph_entry_fields, 1000 true /* is_full_module_graph */); 1001 Modules::verify_archived_modules(); 1002 } 1003 } 1004 1005 // 1006 // Subgraph archiving support 1007 // 1008 HeapShared::DumpTimeKlassSubGraphInfoTable* HeapShared::_dump_time_subgraph_info_table = nullptr; 1009 HeapShared::RunTimeKlassSubGraphInfoTable HeapShared::_run_time_subgraph_info_table; 1010 1011 // Get the subgraph_info for Klass k. A new subgraph_info is created if 1012 // there is no existing one for k. The subgraph_info records the "buffered" 1013 // address of the class. 1014 KlassSubGraphInfo* HeapShared::init_subgraph_info(Klass* k, bool is_full_module_graph) { 1015 assert(CDSConfig::is_dumping_heap(), "dump time only"); 1016 bool created; 1017 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(k); 1018 KlassSubGraphInfo* info = 1019 _dump_time_subgraph_info_table->put_if_absent(k, KlassSubGraphInfo(buffered_k, is_full_module_graph), 1020 &created); 1021 assert(created, "must not initialize twice"); 1022 return info; 1023 } 1024 1025 KlassSubGraphInfo* HeapShared::get_subgraph_info(Klass* k) { 1026 assert(CDSConfig::is_dumping_heap(), "dump time only"); 1027 KlassSubGraphInfo* info = _dump_time_subgraph_info_table->get(k); 1028 assert(info != nullptr, "must have been initialized"); 1029 return info; 1030 } 1031 1032 // Add an entry field to the current KlassSubGraphInfo. 1033 void KlassSubGraphInfo::add_subgraph_entry_field(int static_field_offset, oop v) { 1034 assert(CDSConfig::is_dumping_heap(), "dump time only"); 1035 if (_subgraph_entry_fields == nullptr) { 1036 _subgraph_entry_fields = 1037 new (mtClass) GrowableArray<int>(10, mtClass); 1038 } 1039 _subgraph_entry_fields->append(static_field_offset); 1040 _subgraph_entry_fields->append(HeapShared::append_root(v)); 1041 } 1042 1043 // Add the Klass* for an object in the current KlassSubGraphInfo's subgraphs. 1044 // Only objects of boot classes can be included in sub-graph. 1045 void KlassSubGraphInfo::add_subgraph_object_klass(Klass* orig_k) { 1046 assert(CDSConfig::is_dumping_heap(), "dump time only"); 1047 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(orig_k); 1048 1049 if (_subgraph_object_klasses == nullptr) { 1050 _subgraph_object_klasses = 1051 new (mtClass) GrowableArray<Klass*>(50, mtClass); 1052 } 1053 1054 assert(ArchiveBuilder::current()->is_in_buffer_space(buffered_k), "must be a shared class"); 1055 1056 if (_k == buffered_k) { 1057 // Don't add the Klass containing the sub-graph to it's own klass 1058 // initialization list. 1059 return; 1060 } 1061 1062 if (buffered_k->is_instance_klass()) { 1063 if (CDSConfig::is_dumping_invokedynamic()) { 1064 assert(InstanceKlass::cast(buffered_k)->is_shared_boot_class() || 1065 HeapShared::is_lambda_proxy_klass(InstanceKlass::cast(buffered_k)), 1066 "we can archive only instances of boot classes or lambda proxy classes"); 1067 } else { 1068 assert(InstanceKlass::cast(buffered_k)->is_shared_boot_class(), 1069 "must be boot class"); 1070 } 1071 // vmClasses::xxx_klass() are not updated, need to check 1072 // the original Klass* 1073 if (orig_k == vmClasses::String_klass() || 1074 orig_k == vmClasses::Object_klass()) { 1075 // Initialized early during VM initialization. No need to be added 1076 // to the sub-graph object class list. 1077 return; 1078 } 1079 check_allowed_klass(InstanceKlass::cast(orig_k)); 1080 } else if (buffered_k->is_objArray_klass()) { 1081 Klass* abk = ObjArrayKlass::cast(buffered_k)->bottom_klass(); 1082 if (abk->is_instance_klass()) { 1083 assert(InstanceKlass::cast(abk)->is_shared_boot_class(), 1084 "must be boot class"); 1085 check_allowed_klass(InstanceKlass::cast(ObjArrayKlass::cast(orig_k)->bottom_klass())); 1086 } 1087 if (buffered_k == Universe::objectArrayKlass()) { 1088 // Initialized early during Universe::genesis. No need to be added 1089 // to the list. 1090 return; 1091 } 1092 } else { 1093 assert(buffered_k->is_typeArray_klass(), "must be"); 1094 // Primitive type arrays are created early during Universe::genesis. 1095 return; 1096 } 1097 1098 if (log_is_enabled(Debug, cds, heap)) { 1099 if (!_subgraph_object_klasses->contains(buffered_k)) { 1100 ResourceMark rm; 1101 log_debug(cds, heap)("Adding klass %s", orig_k->external_name()); 1102 } 1103 } 1104 1105 _subgraph_object_klasses->append_if_missing(buffered_k); 1106 _has_non_early_klasses |= is_non_early_klass(orig_k); 1107 } 1108 1109 void KlassSubGraphInfo::check_allowed_klass(InstanceKlass* ik) { 1110 if (CDSConfig::is_dumping_invokedynamic()) { 1111 // FIXME -- this allows LambdaProxy classes 1112 return; 1113 } 1114 if (ik->module()->name() == vmSymbols::java_base()) { 1115 assert(ik->package() != nullptr, "classes in java.base cannot be in unnamed package"); 1116 return; 1117 } 1118 1119 #ifndef PRODUCT 1120 if (!ik->module()->is_named() && ik->package() == nullptr) { 1121 // This class is loaded by ArchiveHeapTestClass 1122 return; 1123 } 1124 const char* extra_msg = ", or in an unnamed package of an unnamed module"; 1125 #else 1126 const char* extra_msg = ""; 1127 #endif 1128 1129 ResourceMark rm; 1130 log_error(cds, heap)("Class %s not allowed in archive heap. Must be in java.base%s", 1131 ik->external_name(), extra_msg); 1132 MetaspaceShared::unrecoverable_writing_error(); 1133 } 1134 1135 bool KlassSubGraphInfo::is_non_early_klass(Klass* k) { 1136 if (k->is_objArray_klass()) { 1137 k = ObjArrayKlass::cast(k)->bottom_klass(); 1138 } 1139 if (k->is_instance_klass()) { 1140 if (!SystemDictionaryShared::is_early_klass(InstanceKlass::cast(k))) { 1141 ResourceMark rm; 1142 log_info(cds, heap)("non-early: %s", k->external_name()); 1143 return true; 1144 } else { 1145 return false; 1146 } 1147 } else { 1148 return false; 1149 } 1150 } 1151 1152 // Initialize an archived subgraph_info_record from the given KlassSubGraphInfo. 1153 void ArchivedKlassSubGraphInfoRecord::init(KlassSubGraphInfo* info) { 1154 _k = info->klass(); 1155 _entry_field_records = nullptr; 1156 _subgraph_object_klasses = nullptr; 1157 _is_full_module_graph = info->is_full_module_graph(); 1158 1159 if (_is_full_module_graph) { 1160 // Consider all classes referenced by the full module graph as early -- we will be 1161 // allocating objects of these classes during JVMTI early phase, so they cannot 1162 // be processed by (non-early) JVMTI ClassFileLoadHook 1163 _has_non_early_klasses = false; 1164 } else { 1165 _has_non_early_klasses = info->has_non_early_klasses(); 1166 } 1167 1168 if (_has_non_early_klasses) { 1169 ResourceMark rm; 1170 log_info(cds, heap)( 1171 "Subgraph of klass %s has non-early klasses and cannot be used when JVMTI ClassFileLoadHook is enabled", 1172 _k->external_name()); 1173 } 1174 1175 // populate the entry fields 1176 GrowableArray<int>* entry_fields = info->subgraph_entry_fields(); 1177 if (entry_fields != nullptr) { 1178 int num_entry_fields = entry_fields->length(); 1179 assert(num_entry_fields % 2 == 0, "sanity"); 1180 _entry_field_records = 1181 ArchiveBuilder::new_ro_array<int>(num_entry_fields); 1182 for (int i = 0 ; i < num_entry_fields; i++) { 1183 _entry_field_records->at_put(i, entry_fields->at(i)); 1184 } 1185 } 1186 1187 // the Klasses of the objects in the sub-graphs 1188 GrowableArray<Klass*>* subgraph_object_klasses = info->subgraph_object_klasses(); 1189 if (subgraph_object_klasses != nullptr) { 1190 int num_subgraphs_klasses = subgraph_object_klasses->length(); 1191 _subgraph_object_klasses = 1192 ArchiveBuilder::new_ro_array<Klass*>(num_subgraphs_klasses); 1193 for (int i = 0; i < num_subgraphs_klasses; i++) { 1194 Klass* subgraph_k = subgraph_object_klasses->at(i); 1195 if (log_is_enabled(Info, cds, heap)) { 1196 ResourceMark rm; 1197 log_info(cds, heap)( 1198 "Archived object klass %s (%2d) => %s", 1199 _k->external_name(), i, subgraph_k->external_name()); 1200 } 1201 _subgraph_object_klasses->at_put(i, subgraph_k); 1202 ArchivePtrMarker::mark_pointer(_subgraph_object_klasses->adr_at(i)); 1203 } 1204 } 1205 1206 ArchivePtrMarker::mark_pointer(&_k); 1207 ArchivePtrMarker::mark_pointer(&_entry_field_records); 1208 ArchivePtrMarker::mark_pointer(&_subgraph_object_klasses); 1209 } 1210 1211 class HeapShared::CopyKlassSubGraphInfoToArchive : StackObj { 1212 CompactHashtableWriter* _writer; 1213 public: 1214 CopyKlassSubGraphInfoToArchive(CompactHashtableWriter* writer) : _writer(writer) {} 1215 1216 bool do_entry(Klass* klass, KlassSubGraphInfo& info) { 1217 if (info.subgraph_object_klasses() != nullptr || info.subgraph_entry_fields() != nullptr) { 1218 ArchivedKlassSubGraphInfoRecord* record = HeapShared::archive_subgraph_info(&info); 1219 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(klass); 1220 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary((address)buffered_k); 1221 u4 delta = ArchiveBuilder::current()->any_to_offset_u4(record); 1222 _writer->add(hash, delta); 1223 } 1224 return true; // keep on iterating 1225 } 1226 }; 1227 1228 ArchivedKlassSubGraphInfoRecord* HeapShared::archive_subgraph_info(KlassSubGraphInfo* info) { 1229 ArchivedKlassSubGraphInfoRecord* record = 1230 (ArchivedKlassSubGraphInfoRecord*)ArchiveBuilder::ro_region_alloc(sizeof(ArchivedKlassSubGraphInfoRecord)); 1231 record->init(info); 1232 if (info == _default_subgraph_info) { 1233 _runtime_default_subgraph_info = record; 1234 } 1235 return record; 1236 } 1237 1238 // Build the records of archived subgraph infos, which include: 1239 // - Entry points to all subgraphs from the containing class mirror. The entry 1240 // points are static fields in the mirror. For each entry point, the field 1241 // offset, and value are recorded in the sub-graph 1242 // info. The value is stored back to the corresponding field at runtime. 1243 // - A list of klasses that need to be loaded/initialized before archived 1244 // java object sub-graph can be accessed at runtime. 1245 void HeapShared::write_subgraph_info_table() { 1246 // Allocate the contents of the hashtable(s) inside the RO region of the CDS archive. 1247 DumpTimeKlassSubGraphInfoTable* d_table = _dump_time_subgraph_info_table; 1248 CompactHashtableStats stats; 1249 1250 _run_time_subgraph_info_table.reset(); 1251 1252 CompactHashtableWriter writer(d_table->_count, &stats); 1253 CopyKlassSubGraphInfoToArchive copy(&writer); 1254 d_table->iterate(©); 1255 writer.dump(&_run_time_subgraph_info_table, "subgraphs"); 1256 1257 #ifndef PRODUCT 1258 if (ArchiveHeapTestClass != nullptr) { 1259 size_t len = strlen(ArchiveHeapTestClass) + 1; 1260 Array<char>* array = ArchiveBuilder::new_ro_array<char>((int)len); 1261 strncpy(array->adr_at(0), ArchiveHeapTestClass, len); 1262 _archived_ArchiveHeapTestClass = array; 1263 } 1264 #endif 1265 if (log_is_enabled(Info, cds, heap)) { 1266 print_stats(); 1267 } 1268 } 1269 1270 void HeapShared::add_root_segment(objArrayOop segment_oop) { 1271 assert(segment_oop != nullptr, "must be"); 1272 assert(ArchiveHeapLoader::is_in_use(), "must be"); 1273 if (_root_segments == nullptr) { 1274 _root_segments = new GrowableArrayCHeap<OopHandle, mtClassShared>(10); 1275 } 1276 _root_segments->push(OopHandle(Universe::vm_global(), segment_oop)); 1277 } 1278 1279 void HeapShared::init_root_segment_sizes(int max_size_elems) { 1280 _root_segment_max_size_elems = max_size_elems; 1281 } 1282 1283 void HeapShared::serialize_tables(SerializeClosure* soc) { 1284 1285 #ifndef PRODUCT 1286 soc->do_ptr(&_archived_ArchiveHeapTestClass); 1287 if (soc->reading() && _archived_ArchiveHeapTestClass != nullptr) { 1288 _test_class_name = _archived_ArchiveHeapTestClass->adr_at(0); 1289 setup_test_class(_test_class_name); 1290 } 1291 #endif 1292 1293 _run_time_subgraph_info_table.serialize_header(soc); 1294 soc->do_ptr(&_runtime_default_subgraph_info); 1295 } 1296 1297 static void verify_the_heap(Klass* k, const char* which) { 1298 if (VerifyArchivedFields > 0) { 1299 ResourceMark rm; 1300 log_info(cds, heap)("Verify heap %s initializing static field(s) in %s", 1301 which, k->external_name()); 1302 1303 VM_Verify verify_op; 1304 VMThread::execute(&verify_op); 1305 1306 if (VerifyArchivedFields > 1 && is_init_completed()) { 1307 // At this time, the oop->klass() of some archived objects in the heap may not 1308 // have been loaded into the system dictionary yet. Nevertheless, oop->klass() should 1309 // have enough information (object size, oop maps, etc) so that a GC can be safely 1310 // performed. 1311 // 1312 // -XX:VerifyArchivedFields=2 force a GC to happen in such an early stage 1313 // to check for GC safety. 1314 log_info(cds, heap)("Trigger GC %s initializing static field(s) in %s", 1315 which, k->external_name()); 1316 FlagSetting fs1(VerifyBeforeGC, true); 1317 FlagSetting fs2(VerifyDuringGC, true); 1318 FlagSetting fs3(VerifyAfterGC, true); 1319 Universe::heap()->collect(GCCause::_java_lang_system_gc); 1320 } 1321 } 1322 } 1323 1324 // Before GC can execute, we must ensure that all oops reachable from HeapShared::roots() 1325 // have a valid klass. I.e., oopDesc::klass() must have already been resolved. 1326 // 1327 // Note: if a ArchivedKlassSubGraphInfoRecord contains non-early classes, and JVMTI 1328 // ClassFileLoadHook is enabled, it's possible for this class to be dynamically replaced. In 1329 // this case, we will not load the ArchivedKlassSubGraphInfoRecord and will clear its roots. 1330 void HeapShared::resolve_classes(JavaThread* current) { 1331 assert(CDSConfig::is_using_archive(), "runtime only!"); 1332 if (!ArchiveHeapLoader::is_in_use()) { 1333 return; // nothing to do 1334 } 1335 1336 if (!CDSConfig::is_using_aot_linked_classes()) { 1337 assert( _runtime_default_subgraph_info != nullptr, "must be"); 1338 Array<Klass*>* klasses = _runtime_default_subgraph_info->subgraph_object_klasses(); 1339 if (klasses != nullptr) { 1340 for (int i = 0; i < klasses->length(); i++) { 1341 Klass* k = klasses->at(i); 1342 ExceptionMark em(current); // no exception can happen here 1343 resolve_or_init(k, /*do_init*/false, current); 1344 } 1345 } 1346 } 1347 1348 resolve_classes_for_subgraphs(current, archive_subgraph_entry_fields); 1349 resolve_classes_for_subgraphs(current, fmg_archive_subgraph_entry_fields); 1350 } 1351 1352 void HeapShared::resolve_classes_for_subgraphs(JavaThread* current, ArchivableStaticFieldInfo fields[]) { 1353 for (int i = 0; fields[i].valid(); i++) { 1354 ArchivableStaticFieldInfo* info = &fields[i]; 1355 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name); 1356 InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name); 1357 assert(k != nullptr && k->is_shared_boot_class(), "sanity"); 1358 resolve_classes_for_subgraph_of(current, k); 1359 } 1360 } 1361 1362 void HeapShared::resolve_classes_for_subgraph_of(JavaThread* current, Klass* k) { 1363 JavaThread* THREAD = current; 1364 ExceptionMark em(THREAD); 1365 const ArchivedKlassSubGraphInfoRecord* record = 1366 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD); 1367 if (HAS_PENDING_EXCEPTION) { 1368 CLEAR_PENDING_EXCEPTION; 1369 } 1370 if (record == nullptr) { 1371 clear_archived_roots_of(k); 1372 } 1373 } 1374 1375 void HeapShared::initialize_java_lang_invoke(TRAPS) { 1376 if (CDSConfig::is_loading_invokedynamic() || CDSConfig::is_dumping_invokedynamic()) { 1377 resolve_or_init("java/lang/invoke/Invokers$Holder", true, CHECK); 1378 resolve_or_init("java/lang/invoke/MethodHandle", true, CHECK); 1379 resolve_or_init("java/lang/invoke/MethodHandleNatives", true, CHECK); 1380 resolve_or_init("java/lang/invoke/DirectMethodHandle$Holder", true, CHECK); 1381 resolve_or_init("java/lang/invoke/DelegatingMethodHandle$Holder", true, CHECK); 1382 resolve_or_init("java/lang/invoke/LambdaForm$Holder", true, CHECK); 1383 resolve_or_init("java/lang/invoke/BoundMethodHandle$Species_L", true, CHECK); 1384 } 1385 } 1386 1387 void HeapShared::initialize_default_subgraph_classes(Handle class_loader, TRAPS) { 1388 if (!ArchiveHeapLoader::is_in_use()) { 1389 return; 1390 } 1391 1392 assert( _runtime_default_subgraph_info != nullptr, "must be"); 1393 Array<Klass*>* klasses = _runtime_default_subgraph_info->subgraph_object_klasses(); 1394 if (klasses != nullptr) { 1395 for (int pass = 0; pass < 2; pass ++) { 1396 for (int i = 0; i < klasses->length(); i++) { 1397 Klass* k = klasses->at(i); 1398 if (k->class_loader_data() == nullptr) { 1399 // This class is not yet loaded. We will initialize it in a later phase. 1400 continue; 1401 } 1402 if (k->class_loader() == class_loader()) { 1403 if (pass == 0) { 1404 if (k->is_instance_klass()) { 1405 InstanceKlass::cast(k)->link_class(CHECK); 1406 } 1407 } else { 1408 resolve_or_init(k, /*do_init*/true, CHECK); 1409 } 1410 } 1411 } 1412 } 1413 } 1414 } 1415 1416 void HeapShared::initialize_from_archived_subgraph(JavaThread* current, Klass* k) { 1417 JavaThread* THREAD = current; 1418 if (!ArchiveHeapLoader::is_in_use()) { 1419 return; // nothing to do 1420 } 1421 1422 if (k->name()->equals("jdk/internal/module/ArchivedModuleGraph") && 1423 !CDSConfig::is_using_optimized_module_handling() && 1424 // archive was created with --module-path 1425 ClassLoaderExt::num_module_paths() > 0) { 1426 // ArchivedModuleGraph was created with a --module-path that's different than the runtime --module-path. 1427 // Thus, it might contain references to modules that do not exist at runtime. We cannot use it. 1428 log_info(cds, heap)("Skip initializing ArchivedModuleGraph subgraph: is_using_optimized_module_handling=%s num_module_paths=%d", 1429 BOOL_TO_STR(CDSConfig::is_using_optimized_module_handling()), ClassLoaderExt::num_module_paths()); 1430 return; 1431 } 1432 1433 ExceptionMark em(THREAD); 1434 const ArchivedKlassSubGraphInfoRecord* record = 1435 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD); 1436 1437 if (HAS_PENDING_EXCEPTION) { 1438 CLEAR_PENDING_EXCEPTION; 1439 // None of the field value will be set if there was an exception when initializing the classes. 1440 // The java code will not see any of the archived objects in the 1441 // subgraphs referenced from k in this case. 1442 return; 1443 } 1444 1445 if (record != nullptr) { 1446 init_archived_fields_for(k, record); 1447 } 1448 } 1449 1450 const ArchivedKlassSubGraphInfoRecord* 1451 HeapShared::resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS) { 1452 assert(!CDSConfig::is_dumping_heap(), "Should not be called when dumping heap"); 1453 1454 if (!k->is_shared()) { 1455 return nullptr; 1456 } 1457 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k); 1458 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0); 1459 1460 #ifndef PRODUCT 1461 if (_test_class_name != nullptr && k->name()->equals(_test_class_name) && record != nullptr) { 1462 _test_class = k; 1463 _test_class_record = record; 1464 } 1465 #endif 1466 1467 // Initialize from archived data. Currently this is done only 1468 // during VM initialization time. No lock is needed. 1469 if (record == nullptr) { 1470 if (log_is_enabled(Info, cds, heap)) { 1471 ResourceMark rm(THREAD); 1472 log_info(cds, heap)("subgraph %s is not recorded", 1473 k->external_name()); 1474 } 1475 return nullptr; 1476 } else { 1477 if (record->is_full_module_graph() && !CDSConfig::is_using_full_module_graph()) { 1478 if (log_is_enabled(Info, cds, heap)) { 1479 ResourceMark rm(THREAD); 1480 log_info(cds, heap)("subgraph %s cannot be used because full module graph is disabled", 1481 k->external_name()); 1482 } 1483 return nullptr; 1484 } 1485 1486 if (record->has_non_early_klasses() && JvmtiExport::should_post_class_file_load_hook()) { 1487 if (log_is_enabled(Info, cds, heap)) { 1488 ResourceMark rm(THREAD); 1489 log_info(cds, heap)("subgraph %s cannot be used because JVMTI ClassFileLoadHook is enabled", 1490 k->external_name()); 1491 } 1492 return nullptr; 1493 } 1494 1495 if (log_is_enabled(Info, cds, heap)) { 1496 ResourceMark rm; 1497 log_info(cds, heap)("%s subgraph %s ", do_init ? "init" : "resolve", k->external_name()); 1498 } 1499 1500 resolve_or_init(k, do_init, CHECK_NULL); 1501 1502 // Load/link/initialize the klasses of the objects in the subgraph. 1503 // nullptr class loader is used. 1504 Array<Klass*>* klasses = record->subgraph_object_klasses(); 1505 if (klasses != nullptr) { 1506 for (int i = 0; i < klasses->length(); i++) { 1507 Klass* klass = klasses->at(i); 1508 if (!klass->is_shared()) { 1509 return nullptr; 1510 } 1511 resolve_or_init(klass, do_init, CHECK_NULL); 1512 } 1513 } 1514 } 1515 1516 return record; 1517 } 1518 1519 void HeapShared::resolve_or_init(const char* klass_name, bool do_init, TRAPS) { 1520 TempNewSymbol klass_name_sym = SymbolTable::new_symbol(klass_name); 1521 InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name_sym); 1522 if (k == nullptr) { 1523 return; 1524 } 1525 assert(k->is_shared_boot_class(), "sanity"); 1526 resolve_or_init(k, false, CHECK); 1527 if (do_init) { 1528 resolve_or_init(k, true, CHECK); 1529 } 1530 } 1531 1532 void HeapShared::resolve_or_init(Klass* k, bool do_init, TRAPS) { 1533 if (!do_init) { 1534 if (k->class_loader_data() == nullptr) { 1535 Klass* resolved_k = SystemDictionary::resolve_or_null(k->name(), CHECK); 1536 assert(resolved_k == k, "classes used by archived heap must not be replaced by JVMTI ClassFileLoadHook"); 1537 } 1538 } else { 1539 assert(k->class_loader_data() != nullptr, "must have been resolved by HeapShared::resolve_classes"); 1540 if (k->is_instance_klass()) { 1541 InstanceKlass* ik = InstanceKlass::cast(k); 1542 ik->initialize(CHECK); 1543 } else if (k->is_objArray_klass()) { 1544 ObjArrayKlass* oak = ObjArrayKlass::cast(k); 1545 oak->initialize(CHECK); 1546 } 1547 } 1548 } 1549 1550 void HeapShared::init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record) { 1551 verify_the_heap(k, "before"); 1552 1553 // Load the subgraph entry fields from the record and store them back to 1554 // the corresponding fields within the mirror. 1555 oop m = k->java_mirror(); 1556 Array<int>* entry_field_records = record->entry_field_records(); 1557 if (entry_field_records != nullptr) { 1558 int efr_len = entry_field_records->length(); 1559 assert(efr_len % 2 == 0, "sanity"); 1560 for (int i = 0; i < efr_len; i += 2) { 1561 int field_offset = entry_field_records->at(i); 1562 int root_index = entry_field_records->at(i+1); 1563 oop v = get_root(root_index, /*clear=*/true); 1564 m->obj_field_put(field_offset, v); 1565 log_debug(cds, heap)(" " PTR_FORMAT " init field @ %2d = " PTR_FORMAT, p2i(k), field_offset, p2i(v)); 1566 } 1567 1568 // Done. Java code can see the archived sub-graphs referenced from k's 1569 // mirror after this point. 1570 if (log_is_enabled(Info, cds, heap)) { 1571 ResourceMark rm; 1572 log_info(cds, heap)("initialize_from_archived_subgraph %s " PTR_FORMAT "%s", 1573 k->external_name(), p2i(k), JvmtiExport::is_early_phase() ? " (early)" : ""); 1574 } 1575 } 1576 1577 verify_the_heap(k, "after "); 1578 } 1579 1580 void HeapShared::clear_archived_roots_of(Klass* k) { 1581 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k); 1582 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0); 1583 if (record != nullptr) { 1584 Array<int>* entry_field_records = record->entry_field_records(); 1585 if (entry_field_records != nullptr) { 1586 int efr_len = entry_field_records->length(); 1587 assert(efr_len % 2 == 0, "sanity"); 1588 for (int i = 0; i < efr_len; i += 2) { 1589 int root_index = entry_field_records->at(i+1); 1590 clear_root(root_index); 1591 } 1592 } 1593 } 1594 } 1595 1596 class WalkOopAndArchiveClosure: public BasicOopIterateClosure { 1597 int _level; 1598 bool _record_klasses_only; 1599 KlassSubGraphInfo* _subgraph_info; 1600 oop _referencing_obj; 1601 1602 // The following are for maintaining a stack for determining 1603 // CachedOopInfo::_referrer 1604 static WalkOopAndArchiveClosure* _current; 1605 WalkOopAndArchiveClosure* _last; 1606 public: 1607 WalkOopAndArchiveClosure(int level, 1608 bool record_klasses_only, 1609 KlassSubGraphInfo* subgraph_info, 1610 oop orig) : 1611 _level(level), 1612 _record_klasses_only(record_klasses_only), 1613 _subgraph_info(subgraph_info), 1614 _referencing_obj(orig) { 1615 _last = _current; 1616 _current = this; 1617 } 1618 ~WalkOopAndArchiveClosure() { 1619 _current = _last; 1620 } 1621 void do_oop(narrowOop *p) { WalkOopAndArchiveClosure::do_oop_work(p); } 1622 void do_oop( oop *p) { WalkOopAndArchiveClosure::do_oop_work(p); } 1623 1624 protected: 1625 template <class T> void do_oop_work(T *p) { 1626 oop obj = RawAccess<>::oop_load(p); 1627 if (!CompressedOops::is_null(obj)) { 1628 size_t field_delta = pointer_delta(p, _referencing_obj, sizeof(char)); 1629 1630 if (!_record_klasses_only && log_is_enabled(Debug, cds, heap)) { 1631 ResourceMark rm; 1632 log_debug(cds, heap)("(%d) %s[" SIZE_FORMAT "] ==> " PTR_FORMAT " size " SIZE_FORMAT " %s", _level, 1633 _referencing_obj->klass()->external_name(), field_delta, 1634 p2i(obj), obj->size() * HeapWordSize, obj->klass()->external_name()); 1635 if (log_is_enabled(Trace, cds, heap)) { 1636 LogTarget(Trace, cds, heap) log; 1637 LogStream out(log); 1638 obj->print_on(&out); 1639 } 1640 } 1641 1642 bool success = HeapShared::archive_reachable_objects_from( 1643 _level + 1, _subgraph_info, obj); 1644 assert(success, "VM should have exited with unarchivable objects for _level > 1"); 1645 } 1646 } 1647 1648 public: 1649 static WalkOopAndArchiveClosure* current() { return _current; } 1650 oop referencing_obj() { return _referencing_obj; } 1651 KlassSubGraphInfo* subgraph_info() { return _subgraph_info; } 1652 }; 1653 1654 WalkOopAndArchiveClosure* WalkOopAndArchiveClosure::_current = nullptr; 1655 1656 // Checks if an oop has any non-null oop fields 1657 class PointsToOopsChecker : public BasicOopIterateClosure { 1658 bool _result; 1659 1660 template <class T> void check(T *p) { 1661 _result |= (HeapAccess<>::oop_load(p) != nullptr); 1662 } 1663 1664 public: 1665 PointsToOopsChecker() : _result(false) {} 1666 void do_oop(narrowOop *p) { check(p); } 1667 void do_oop( oop *p) { check(p); } 1668 bool result() { return _result; } 1669 }; 1670 1671 HeapShared::CachedOopInfo HeapShared::make_cached_oop_info(oop obj) { 1672 WalkOopAndArchiveClosure* walker = WalkOopAndArchiveClosure::current(); 1673 oop referrer = (walker == nullptr) ? nullptr : walker->referencing_obj(); 1674 PointsToOopsChecker points_to_oops_checker; 1675 obj->oop_iterate(&points_to_oops_checker); 1676 return CachedOopInfo(referrer, points_to_oops_checker.result()); 1677 } 1678 1679 // We currently allow only the box classes, as well as j.l.Object, which are 1680 // initialized very early by HeapShared::init_box_classes(). 1681 bool HeapShared::can_mirror_be_used_in_subgraph(oop orig_java_mirror) { 1682 return java_lang_Class::is_primitive(orig_java_mirror) 1683 || orig_java_mirror == vmClasses::Boolean_klass()->java_mirror() 1684 || orig_java_mirror == vmClasses::Character_klass()->java_mirror() 1685 || orig_java_mirror == vmClasses::Float_klass()->java_mirror() 1686 || orig_java_mirror == vmClasses::Double_klass()->java_mirror() 1687 || orig_java_mirror == vmClasses::Byte_klass()->java_mirror() 1688 || orig_java_mirror == vmClasses::Short_klass()->java_mirror() 1689 || orig_java_mirror == vmClasses::Integer_klass()->java_mirror() 1690 || orig_java_mirror == vmClasses::Long_klass()->java_mirror() 1691 || orig_java_mirror == vmClasses::Void_klass()->java_mirror() 1692 || orig_java_mirror == vmClasses::Object_klass()->java_mirror(); 1693 } 1694 1695 void HeapShared::init_box_classes(TRAPS) { 1696 if (ArchiveHeapLoader::is_in_use()) { 1697 vmClasses::Boolean_klass()->initialize(CHECK); 1698 vmClasses::Character_klass()->initialize(CHECK); 1699 vmClasses::Float_klass()->initialize(CHECK); 1700 vmClasses::Double_klass()->initialize(CHECK); 1701 vmClasses::Byte_klass()->initialize(CHECK); 1702 vmClasses::Short_klass()->initialize(CHECK); 1703 vmClasses::Integer_klass()->initialize(CHECK); 1704 vmClasses::Long_klass()->initialize(CHECK); 1705 vmClasses::Void_klass()->initialize(CHECK); 1706 } 1707 } 1708 1709 void HeapShared::exit_on_error() { 1710 if (_context != nullptr) { 1711 ResourceMark rm; 1712 LogStream ls(Log(cds, heap)::error()); 1713 ls.print_cr("Context"); 1714 for (int i = 0; i < _context->length(); i++) { 1715 const char* s = _context->at(i); 1716 ls.print_cr("- %s", s); 1717 } 1718 } 1719 if (_trace != nullptr) { 1720 ResourceMark rm; 1721 LogStream ls(Log(cds, heap)::error()); 1722 ls.print_cr("Reference trace"); 1723 for (int i = 0; i < _trace->length(); i++) { 1724 oop orig_obj = _trace->at(i); 1725 ls.print_cr("[%d] ========================================", i); 1726 orig_obj->print_on(&ls); 1727 ls.cr(); 1728 } 1729 } 1730 MetaspaceShared::unrecoverable_writing_error(); 1731 } 1732 1733 void HeapShared::debug_trace() { 1734 WalkOopAndArchiveClosure* walker = WalkOopAndArchiveClosure::current(); 1735 if (walker != nullptr) { 1736 LogStream ls(Log(cds, heap)::error()); 1737 CDSHeapVerifier::trace_to_root(&ls, walker->referencing_obj()); 1738 } 1739 } 1740 1741 // (1) If orig_obj has not been archived yet, archive it. 1742 // (2) If orig_obj has not been seen yet (since start_recording_subgraph() was called), 1743 // trace all objects that are reachable from it, and make sure these objects are archived. 1744 // (3) Record the klasses of all orig_obj and all reachable objects. 1745 bool HeapShared::archive_reachable_objects_from(int level, 1746 KlassSubGraphInfo* subgraph_info, 1747 oop orig_obj) { 1748 ArchivingObjectMark mark(orig_obj); 1749 assert(orig_obj != nullptr, "must be"); 1750 1751 if (!JavaClasses::is_supported_for_archiving(orig_obj)) { 1752 // This object has injected fields that cannot be supported easily, so we disallow them for now. 1753 // If you get an error here, you probably made a change in the JDK library that has added 1754 // these objects that are referenced (directly or indirectly) by static fields. 1755 ResourceMark rm; 1756 log_error(cds, heap)("Cannot archive object " PTR_FORMAT " of class %s", p2i(orig_obj), orig_obj->klass()->external_name()); 1757 debug_trace(); 1758 exit_on_error(); 1759 } 1760 1761 if (log_is_enabled(Debug, cds, heap) && java_lang_Class::is_instance(orig_obj)) { 1762 ResourceMark rm; 1763 LogTarget(Debug, cds, heap) log; 1764 LogStream out(log); 1765 out.print("Found java mirror " PTR_FORMAT " ", p2i(orig_obj)); 1766 Klass* k = java_lang_Class::as_Klass(orig_obj); 1767 if (k != nullptr) { 1768 out.print("%s", k->external_name()); 1769 } else { 1770 out.print("primitive"); 1771 } 1772 out.print_cr("; scratch mirror = " PTR_FORMAT, 1773 p2i(scratch_java_mirror(orig_obj))); 1774 } 1775 1776 if (java_lang_Class::is_instance(orig_obj)) { 1777 orig_obj = scratch_java_mirror(orig_obj); 1778 assert(orig_obj != nullptr, "must be archived"); 1779 } 1780 1781 if (has_been_seen_during_subgraph_recording(orig_obj)) { 1782 // orig_obj has already been archived and traced. Nothing more to do. 1783 return true; 1784 } else { 1785 set_has_been_seen_during_subgraph_recording(orig_obj); 1786 } 1787 1788 bool already_archived = has_been_archived(orig_obj); 1789 bool record_klasses_only = already_archived; 1790 if (!already_archived) { 1791 ++_num_new_archived_objs; 1792 if (!archive_object(orig_obj)) { 1793 // Skip archiving the sub-graph referenced from the current entry field. 1794 ResourceMark rm; 1795 log_error(cds, heap)( 1796 "Cannot archive the sub-graph referenced from %s object (" 1797 PTR_FORMAT ") size " SIZE_FORMAT ", skipped.", 1798 orig_obj->klass()->external_name(), p2i(orig_obj), orig_obj->size() * HeapWordSize); 1799 if (level == 1) { 1800 // Don't archive a subgraph root that's too big. For archives static fields, that's OK 1801 // as the Java code will take care of initializing this field dynamically. 1802 return false; 1803 } else { 1804 // We don't know how to handle an object that has been archived, but some of its reachable 1805 // objects cannot be archived. Bail out for now. We might need to fix this in the future if 1806 // we have a real use case. 1807 exit_on_error(); 1808 } 1809 } 1810 } 1811 1812 Klass *orig_k = orig_obj->klass(); 1813 subgraph_info->add_subgraph_object_klass(orig_k); 1814 1815 WalkOopAndArchiveClosure walker(level, record_klasses_only, subgraph_info, orig_obj); 1816 orig_obj->oop_iterate(&walker); 1817 1818 if (CDSConfig::is_initing_classes_at_dump_time()) { 1819 // The enum klasses are archived with preinitialized mirror. 1820 // See AOTClassInitializer::can_archive_initialized_mirror. 1821 } else { 1822 if (CDSEnumKlass::is_enum_obj(orig_obj)) { 1823 CDSEnumKlass::handle_enum_obj(level + 1, subgraph_info, orig_obj); 1824 } 1825 } 1826 1827 return true; 1828 } 1829 1830 // 1831 // Start from the given static field in a java mirror and archive the 1832 // complete sub-graph of java heap objects that are reached directly 1833 // or indirectly from the starting object by following references. 1834 // Sub-graph archiving restrictions (current): 1835 // 1836 // - All classes of objects in the archived sub-graph (including the 1837 // entry class) must be boot class only. 1838 // - No java.lang.Class instance (java mirror) can be included inside 1839 // an archived sub-graph. Mirror can only be the sub-graph entry object. 1840 // 1841 // The Java heap object sub-graph archiving process (see 1842 // WalkOopAndArchiveClosure): 1843 // 1844 // 1) Java object sub-graph archiving starts from a given static field 1845 // within a Class instance (java mirror). If the static field is a 1846 // reference field and points to a non-null java object, proceed to 1847 // the next step. 1848 // 1849 // 2) Archives the referenced java object. If an archived copy of the 1850 // current object already exists, updates the pointer in the archived 1851 // copy of the referencing object to point to the current archived object. 1852 // Otherwise, proceed to the next step. 1853 // 1854 // 3) Follows all references within the current java object and recursively 1855 // archive the sub-graph of objects starting from each reference. 1856 // 1857 // 4) Updates the pointer in the archived copy of referencing object to 1858 // point to the current archived object. 1859 // 1860 // 5) The Klass of the current java object is added to the list of Klasses 1861 // for loading and initializing before any object in the archived graph can 1862 // be accessed at runtime. 1863 // 1864 void HeapShared::archive_reachable_objects_from_static_field(InstanceKlass *k, 1865 const char* klass_name, 1866 int field_offset, 1867 const char* field_name) { 1868 assert(CDSConfig::is_dumping_heap(), "dump time only"); 1869 assert(k->is_shared_boot_class(), "must be boot class"); 1870 1871 oop m = k->java_mirror(); 1872 1873 KlassSubGraphInfo* subgraph_info = get_subgraph_info(k); 1874 oop f = m->obj_field(field_offset); 1875 1876 log_debug(cds, heap)("Start archiving from: %s::%s (" PTR_FORMAT ")", klass_name, field_name, p2i(f)); 1877 1878 if (!CompressedOops::is_null(f)) { 1879 if (log_is_enabled(Trace, cds, heap)) { 1880 LogTarget(Trace, cds, heap) log; 1881 LogStream out(log); 1882 f->print_on(&out); 1883 } 1884 1885 bool success = archive_reachable_objects_from(1, subgraph_info, f); 1886 if (!success) { 1887 log_error(cds, heap)("Archiving failed %s::%s (some reachable objects cannot be archived)", 1888 klass_name, field_name); 1889 } else { 1890 // Note: the field value is not preserved in the archived mirror. 1891 // Record the field as a new subGraph entry point. The recorded 1892 // information is restored from the archive at runtime. 1893 subgraph_info->add_subgraph_entry_field(field_offset, f); 1894 log_info(cds, heap)("Archived field %s::%s => " PTR_FORMAT, klass_name, field_name, p2i(f)); 1895 } 1896 } else { 1897 // The field contains null, we still need to record the entry point, 1898 // so it can be restored at runtime. 1899 subgraph_info->add_subgraph_entry_field(field_offset, nullptr); 1900 } 1901 } 1902 1903 #ifndef PRODUCT 1904 class VerifySharedOopClosure: public BasicOopIterateClosure { 1905 public: 1906 void do_oop(narrowOop *p) { VerifySharedOopClosure::do_oop_work(p); } 1907 void do_oop( oop *p) { VerifySharedOopClosure::do_oop_work(p); } 1908 1909 protected: 1910 template <class T> void do_oop_work(T *p) { 1911 oop obj = RawAccess<>::oop_load(p); 1912 if (!CompressedOops::is_null(obj)) { 1913 HeapShared::verify_reachable_objects_from(obj); 1914 } 1915 } 1916 }; 1917 1918 void HeapShared::verify_subgraph_from_static_field(InstanceKlass* k, int field_offset) { 1919 assert(CDSConfig::is_dumping_heap(), "dump time only"); 1920 assert(k->is_shared_boot_class(), "must be boot class"); 1921 1922 oop m = k->java_mirror(); 1923 oop f = m->obj_field(field_offset); 1924 if (!CompressedOops::is_null(f)) { 1925 verify_subgraph_from(f); 1926 } 1927 } 1928 1929 void HeapShared::verify_subgraph_from(oop orig_obj) { 1930 if (!has_been_archived(orig_obj)) { 1931 // It's OK for the root of a subgraph to be not archived. See comments in 1932 // archive_reachable_objects_from(). 1933 return; 1934 } 1935 1936 // Verify that all objects reachable from orig_obj are archived. 1937 init_seen_objects_table(); 1938 verify_reachable_objects_from(orig_obj); 1939 delete_seen_objects_table(); 1940 } 1941 1942 void HeapShared::verify_reachable_objects_from(oop obj) { 1943 _num_total_verifications ++; 1944 if (java_lang_Class::is_instance(obj)) { 1945 obj = scratch_java_mirror(obj); 1946 assert(obj != nullptr, "must be"); 1947 } 1948 if (!has_been_seen_during_subgraph_recording(obj)) { 1949 set_has_been_seen_during_subgraph_recording(obj); 1950 assert(has_been_archived(obj), "must be"); 1951 VerifySharedOopClosure walker; 1952 obj->oop_iterate(&walker); 1953 } 1954 } 1955 #endif 1956 1957 // The "default subgraph" contains special objects (see heapShared.hpp) that 1958 // can be accessed before we load any Java classes (including java/lang/Class). 1959 // Make sure that these are only instances of the very few specific types 1960 // that we can handle. 1961 void HeapShared::check_default_subgraph_classes() { 1962 if (CDSConfig::is_initing_classes_at_dump_time()) { 1963 return; 1964 } 1965 1966 GrowableArray<Klass*>* klasses = _default_subgraph_info->subgraph_object_klasses(); 1967 int num = klasses->length(); 1968 for (int i = 0; i < num; i++) { 1969 Klass* subgraph_k = klasses->at(i); 1970 Symbol* name = ArchiveBuilder::current()->get_source_addr(subgraph_k->name()); 1971 if (subgraph_k->is_instance_klass() && 1972 name != vmSymbols::java_lang_Class() && 1973 name != vmSymbols::java_lang_String() && 1974 name != vmSymbols::java_lang_ArithmeticException() && 1975 name != vmSymbols::java_lang_ArrayIndexOutOfBoundsException() && 1976 name != vmSymbols::java_lang_ArrayStoreException() && 1977 name != vmSymbols::java_lang_ClassCastException() && 1978 name != vmSymbols::java_lang_InternalError() && 1979 name != vmSymbols::java_lang_NullPointerException()) { 1980 ResourceMark rm; 1981 fatal("default subgraph cannot have objects of type %s", subgraph_k->external_name()); 1982 } 1983 } 1984 } 1985 1986 HeapShared::SeenObjectsTable* HeapShared::_seen_objects_table = nullptr; 1987 int HeapShared::_num_new_walked_objs; 1988 int HeapShared::_num_new_archived_objs; 1989 int HeapShared::_num_old_recorded_klasses; 1990 1991 int HeapShared::_num_total_subgraph_recordings = 0; 1992 int HeapShared::_num_total_walked_objs = 0; 1993 int HeapShared::_num_total_archived_objs = 0; 1994 int HeapShared::_num_total_recorded_klasses = 0; 1995 int HeapShared::_num_total_verifications = 0; 1996 1997 bool HeapShared::has_been_seen_during_subgraph_recording(oop obj) { 1998 return _seen_objects_table->get(obj) != nullptr; 1999 } 2000 2001 void HeapShared::set_has_been_seen_during_subgraph_recording(oop obj) { 2002 assert(!has_been_seen_during_subgraph_recording(obj), "sanity"); 2003 _seen_objects_table->put_when_absent(obj, true); 2004 _seen_objects_table->maybe_grow(); 2005 ++ _num_new_walked_objs; 2006 } 2007 2008 void HeapShared::start_recording_subgraph(InstanceKlass *k, const char* class_name, bool is_full_module_graph) { 2009 log_info(cds, heap)("Start recording subgraph(s) for archived fields in %s", class_name); 2010 init_subgraph_info(k, is_full_module_graph); 2011 init_seen_objects_table(); 2012 _num_new_walked_objs = 0; 2013 _num_new_archived_objs = 0; 2014 _num_old_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses(); 2015 } 2016 2017 void HeapShared::done_recording_subgraph(InstanceKlass *k, const char* class_name) { 2018 int num_new_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses() - 2019 _num_old_recorded_klasses; 2020 log_info(cds, heap)("Done recording subgraph(s) for archived fields in %s: " 2021 "walked %d objs, archived %d new objs, recorded %d classes", 2022 class_name, _num_new_walked_objs, _num_new_archived_objs, 2023 num_new_recorded_klasses); 2024 2025 delete_seen_objects_table(); 2026 2027 _num_total_subgraph_recordings ++; 2028 _num_total_walked_objs += _num_new_walked_objs; 2029 _num_total_archived_objs += _num_new_archived_objs; 2030 _num_total_recorded_klasses += num_new_recorded_klasses; 2031 } 2032 2033 class ArchivableStaticFieldFinder: public FieldClosure { 2034 InstanceKlass* _ik; 2035 Symbol* _field_name; 2036 bool _found; 2037 int _offset; 2038 public: 2039 ArchivableStaticFieldFinder(InstanceKlass* ik, Symbol* field_name) : 2040 _ik(ik), _field_name(field_name), _found(false), _offset(-1) {} 2041 2042 virtual void do_field(fieldDescriptor* fd) { 2043 if (fd->name() == _field_name) { 2044 assert(!_found, "fields can never be overloaded"); 2045 if (is_reference_type(fd->field_type())) { 2046 _found = true; 2047 _offset = fd->offset(); 2048 } 2049 } 2050 } 2051 bool found() { return _found; } 2052 int offset() { return _offset; } 2053 }; 2054 2055 void HeapShared::init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[], 2056 TRAPS) { 2057 for (int i = 0; fields[i].valid(); i++) { 2058 ArchivableStaticFieldInfo* info = &fields[i]; 2059 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name); 2060 TempNewSymbol field_name = SymbolTable::new_symbol(info->field_name); 2061 ResourceMark rm; // for stringStream::as_string() etc. 2062 2063 #ifndef PRODUCT 2064 bool is_test_class = (ArchiveHeapTestClass != nullptr) && (strcmp(info->klass_name, ArchiveHeapTestClass) == 0); 2065 const char* test_class_name = ArchiveHeapTestClass; 2066 #else 2067 bool is_test_class = false; 2068 const char* test_class_name = ""; // avoid C++ printf checks warnings. 2069 #endif 2070 2071 if (is_test_class) { 2072 log_warning(cds)("Loading ArchiveHeapTestClass %s ...", test_class_name); 2073 } 2074 2075 Klass* k = SystemDictionary::resolve_or_fail(klass_name, true, THREAD); 2076 if (HAS_PENDING_EXCEPTION) { 2077 CLEAR_PENDING_EXCEPTION; 2078 stringStream st; 2079 st.print("Fail to initialize archive heap: %s cannot be loaded by the boot loader", info->klass_name); 2080 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); 2081 } 2082 2083 if (!k->is_instance_klass()) { 2084 stringStream st; 2085 st.print("Fail to initialize archive heap: %s is not an instance class", info->klass_name); 2086 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); 2087 } 2088 2089 InstanceKlass* ik = InstanceKlass::cast(k); 2090 assert(InstanceKlass::cast(ik)->is_shared_boot_class(), 2091 "Only support boot classes"); 2092 2093 if (is_test_class) { 2094 if (ik->module()->is_named()) { 2095 // We don't want ArchiveHeapTestClass to be abused to easily load/initialize arbitrary 2096 // core-lib classes. You need to at least append to the bootclasspath. 2097 stringStream st; 2098 st.print("ArchiveHeapTestClass %s is not in unnamed module", test_class_name); 2099 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); 2100 } 2101 2102 if (ik->package() != nullptr) { 2103 // This restriction makes HeapShared::is_a_test_class_in_unnamed_module() easy. 2104 stringStream st; 2105 st.print("ArchiveHeapTestClass %s is not in unnamed package", test_class_name); 2106 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); 2107 } 2108 } else { 2109 if (ik->module()->name() != vmSymbols::java_base()) { 2110 // We don't want to deal with cases when a module is unavailable at runtime. 2111 // FUTURE -- load from archived heap only when module graph has not changed 2112 // between dump and runtime. 2113 stringStream st; 2114 st.print("%s is not in java.base module", info->klass_name); 2115 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); 2116 } 2117 } 2118 2119 if (is_test_class) { 2120 log_warning(cds)("Initializing ArchiveHeapTestClass %s ...", test_class_name); 2121 } 2122 ik->initialize(CHECK); 2123 2124 ArchivableStaticFieldFinder finder(ik, field_name); 2125 ik->do_local_static_fields(&finder); 2126 if (!finder.found()) { 2127 stringStream st; 2128 st.print("Unable to find the static T_OBJECT field %s::%s", info->klass_name, info->field_name); 2129 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); 2130 } 2131 2132 info->klass = ik; 2133 info->offset = finder.offset(); 2134 } 2135 } 2136 2137 void HeapShared::init_subgraph_entry_fields(TRAPS) { 2138 assert(HeapShared::can_write(), "must be"); 2139 _dump_time_subgraph_info_table = new (mtClass)DumpTimeKlassSubGraphInfoTable(); 2140 init_subgraph_entry_fields(archive_subgraph_entry_fields, CHECK); 2141 if (CDSConfig::is_dumping_full_module_graph()) { 2142 init_subgraph_entry_fields(fmg_archive_subgraph_entry_fields, CHECK); 2143 } 2144 } 2145 2146 #ifndef PRODUCT 2147 void HeapShared::setup_test_class(const char* test_class_name) { 2148 ArchivableStaticFieldInfo* p = archive_subgraph_entry_fields; 2149 int num_slots = sizeof(archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo); 2150 assert(p[num_slots - 2].klass_name == nullptr, "must have empty slot that's patched below"); 2151 assert(p[num_slots - 1].klass_name == nullptr, "must have empty slot that marks the end of the list"); 2152 2153 if (test_class_name != nullptr) { 2154 p[num_slots - 2].klass_name = test_class_name; 2155 p[num_slots - 2].field_name = ARCHIVE_TEST_FIELD_NAME; 2156 } 2157 } 2158 2159 // See if ik is one of the test classes that are pulled in by -XX:ArchiveHeapTestClass 2160 // during runtime. This may be called before the module system is initialized so 2161 // we cannot rely on InstanceKlass::module(), etc. 2162 bool HeapShared::is_a_test_class_in_unnamed_module(Klass* ik) { 2163 if (_test_class != nullptr) { 2164 if (ik == _test_class) { 2165 return true; 2166 } 2167 Array<Klass*>* klasses = _test_class_record->subgraph_object_klasses(); 2168 if (klasses == nullptr) { 2169 return false; 2170 } 2171 2172 for (int i = 0; i < klasses->length(); i++) { 2173 Klass* k = klasses->at(i); 2174 if (k == ik) { 2175 Symbol* name; 2176 if (k->is_instance_klass()) { 2177 name = InstanceKlass::cast(k)->name(); 2178 } else if (k->is_objArray_klass()) { 2179 Klass* bk = ObjArrayKlass::cast(k)->bottom_klass(); 2180 if (!bk->is_instance_klass()) { 2181 return false; 2182 } 2183 name = bk->name(); 2184 } else { 2185 return false; 2186 } 2187 2188 // See KlassSubGraphInfo::check_allowed_klass() - only two types of 2189 // classes are allowed: 2190 // (A) java.base classes (which must not be in the unnamed module) 2191 // (B) test classes which must be in the unnamed package of the unnamed module. 2192 // So if we see a '/' character in the class name, it must be in (A); 2193 // otherwise it must be in (B). 2194 if (name->index_of_at(0, "/", 1) >= 0) { 2195 return false; // (A) 2196 } 2197 2198 return true; // (B) 2199 } 2200 } 2201 } 2202 2203 return false; 2204 } 2205 2206 void HeapShared::initialize_test_class_from_archive(JavaThread* current) { 2207 Klass* k = _test_class; 2208 if (k != nullptr && ArchiveHeapLoader::is_in_use()) { 2209 JavaThread* THREAD = current; 2210 ExceptionMark em(THREAD); 2211 const ArchivedKlassSubGraphInfoRecord* record = 2212 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD); 2213 2214 // The _test_class is in the unnamed module, so it can't call CDS.initializeFromArchive() 2215 // from its <clinit> method. So we set up its "archivedObjects" field first, before 2216 // calling its <clinit>. This is not strictly clean, but it's a convenient way to write unit 2217 // test cases (see test/hotspot/jtreg/runtime/cds/appcds/cacheObject/ArchiveHeapTestClass.java). 2218 if (record != nullptr) { 2219 init_archived_fields_for(k, record); 2220 } 2221 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD); 2222 } 2223 } 2224 #endif 2225 2226 void HeapShared::init_for_dumping(TRAPS) { 2227 if (HeapShared::can_write()) { 2228 setup_test_class(ArchiveHeapTestClass); 2229 _dumped_interned_strings = new (mtClass)DumpedInternedStrings(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE); 2230 init_subgraph_entry_fields(CHECK); 2231 } 2232 } 2233 2234 void HeapShared::archive_object_subgraphs(ArchivableStaticFieldInfo fields[], 2235 bool is_full_module_graph) { 2236 _num_total_subgraph_recordings = 0; 2237 _num_total_walked_objs = 0; 2238 _num_total_archived_objs = 0; 2239 _num_total_recorded_klasses = 0; 2240 _num_total_verifications = 0; 2241 2242 // For each class X that has one or more archived fields: 2243 // [1] Dump the subgraph of each archived field 2244 // [2] Create a list of all the class of the objects that can be reached 2245 // by any of these static fields. 2246 // At runtime, these classes are initialized before X's archived fields 2247 // are restored by HeapShared::initialize_from_archived_subgraph(). 2248 for (int i = 0; fields[i].valid(); ) { 2249 ArchivableStaticFieldInfo* info = &fields[i]; 2250 const char* klass_name = info->klass_name; 2251 start_recording_subgraph(info->klass, klass_name, is_full_module_graph); 2252 2253 ContextMark cm(klass_name); 2254 // If you have specified consecutive fields of the same klass in 2255 // fields[], these will be archived in the same 2256 // {start_recording_subgraph ... done_recording_subgraph} pass to 2257 // save time. 2258 for (; fields[i].valid(); i++) { 2259 ArchivableStaticFieldInfo* f = &fields[i]; 2260 if (f->klass_name != klass_name) { 2261 break; 2262 } 2263 2264 ContextMark cm(f->field_name); 2265 archive_reachable_objects_from_static_field(f->klass, f->klass_name, 2266 f->offset, f->field_name); 2267 } 2268 done_recording_subgraph(info->klass, klass_name); 2269 } 2270 2271 log_info(cds, heap)("Archived subgraph records = %d", 2272 _num_total_subgraph_recordings); 2273 log_info(cds, heap)(" Walked %d objects", _num_total_walked_objs); 2274 log_info(cds, heap)(" Archived %d objects", _num_total_archived_objs); 2275 log_info(cds, heap)(" Recorded %d klasses", _num_total_recorded_klasses); 2276 2277 #ifndef PRODUCT 2278 for (int i = 0; fields[i].valid(); i++) { 2279 ArchivableStaticFieldInfo* f = &fields[i]; 2280 verify_subgraph_from_static_field(f->klass, f->offset); 2281 } 2282 log_info(cds, heap)(" Verified %d references", _num_total_verifications); 2283 #endif 2284 } 2285 2286 // Not all the strings in the global StringTable are dumped into the archive, because 2287 // some of those strings may be only referenced by classes that are excluded from 2288 // the archive. We need to explicitly mark the strings that are: 2289 // [1] used by classes that WILL be archived; 2290 // [2] included in the SharedArchiveConfigFile. 2291 void HeapShared::add_to_dumped_interned_strings(oop string) { 2292 assert_at_safepoint(); // DumpedInternedStrings uses raw oops 2293 assert(!ArchiveHeapWriter::is_string_too_large_to_archive(string), "must be"); 2294 bool created; 2295 _dumped_interned_strings->put_if_absent(string, true, &created); 2296 if (created) { 2297 _dumped_interned_strings->maybe_grow(); 2298 } 2299 } 2300 2301 #ifndef PRODUCT 2302 // At dump-time, find the location of all the non-null oop pointers in an archived heap 2303 // region. This way we can quickly relocate all the pointers without using 2304 // BasicOopIterateClosure at runtime. 2305 class FindEmbeddedNonNullPointers: public BasicOopIterateClosure { 2306 void* _start; 2307 BitMap *_oopmap; 2308 int _num_total_oops; 2309 int _num_null_oops; 2310 public: 2311 FindEmbeddedNonNullPointers(void* start, BitMap* oopmap) 2312 : _start(start), _oopmap(oopmap), _num_total_oops(0), _num_null_oops(0) {} 2313 2314 virtual void do_oop(narrowOop* p) { 2315 assert(UseCompressedOops, "sanity"); 2316 _num_total_oops ++; 2317 narrowOop v = *p; 2318 if (!CompressedOops::is_null(v)) { 2319 size_t idx = p - (narrowOop*)_start; 2320 _oopmap->set_bit(idx); 2321 } else { 2322 _num_null_oops ++; 2323 } 2324 } 2325 virtual void do_oop(oop* p) { 2326 assert(!UseCompressedOops, "sanity"); 2327 _num_total_oops ++; 2328 if ((*p) != nullptr) { 2329 size_t idx = p - (oop*)_start; 2330 _oopmap->set_bit(idx); 2331 } else { 2332 _num_null_oops ++; 2333 } 2334 } 2335 int num_total_oops() const { return _num_total_oops; } 2336 int num_null_oops() const { return _num_null_oops; } 2337 }; 2338 #endif 2339 2340 void HeapShared::count_allocation(size_t size) { 2341 _total_obj_count ++; 2342 _total_obj_size += size; 2343 for (int i = 0; i < ALLOC_STAT_SLOTS; i++) { 2344 if (size <= (size_t(1) << i)) { 2345 _alloc_count[i] ++; 2346 _alloc_size[i] += size; 2347 return; 2348 } 2349 } 2350 } 2351 2352 static double avg_size(size_t size, size_t count) { 2353 double avg = 0; 2354 if (count > 0) { 2355 avg = double(size * HeapWordSize) / double(count); 2356 } 2357 return avg; 2358 } 2359 2360 void HeapShared::print_stats() { 2361 size_t huge_count = _total_obj_count; 2362 size_t huge_size = _total_obj_size; 2363 2364 for (int i = 0; i < ALLOC_STAT_SLOTS; i++) { 2365 size_t byte_size_limit = (size_t(1) << i) * HeapWordSize; 2366 size_t count = _alloc_count[i]; 2367 size_t size = _alloc_size[i]; 2368 log_info(cds, heap)(SIZE_FORMAT_W(8) " objects are <= " SIZE_FORMAT_W(-6) 2369 " bytes (total " SIZE_FORMAT_W(8) " bytes, avg %8.1f bytes)", 2370 count, byte_size_limit, size * HeapWordSize, avg_size(size, count)); 2371 huge_count -= count; 2372 huge_size -= size; 2373 } 2374 2375 log_info(cds, heap)(SIZE_FORMAT_W(8) " huge objects (total " SIZE_FORMAT_W(8) " bytes" 2376 ", avg %8.1f bytes)", 2377 huge_count, huge_size * HeapWordSize, 2378 avg_size(huge_size, huge_count)); 2379 log_info(cds, heap)(SIZE_FORMAT_W(8) " total objects (total " SIZE_FORMAT_W(8) " bytes" 2380 ", avg %8.1f bytes)", 2381 _total_obj_count, _total_obj_size * HeapWordSize, 2382 avg_size(_total_obj_size, _total_obj_count)); 2383 } 2384 2385 bool HeapShared::is_archived_boot_layer_available(JavaThread* current) { 2386 TempNewSymbol klass_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_CLASS); 2387 InstanceKlass* k = SystemDictionary::find_instance_klass(current, klass_name, Handle(), Handle()); 2388 if (k == nullptr) { 2389 return false; 2390 } else { 2391 TempNewSymbol field_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_FIELD); 2392 TempNewSymbol field_signature = SymbolTable::new_symbol("Ljdk/internal/module/ArchivedBootLayer;"); 2393 fieldDescriptor fd; 2394 if (k->find_field(field_name, field_signature, true, &fd) != nullptr) { 2395 oop m = k->java_mirror(); 2396 oop f = m->obj_field(fd.offset()); 2397 if (CompressedOops::is_null(f)) { 2398 return false; 2399 } 2400 } else { 2401 return false; 2402 } 2403 } 2404 return true; 2405 } 2406 2407 #endif // INCLUDE_CDS_JAVA_HEAP